Search Results

Search found 13634 results on 546 pages for 'memory cards'.

Page 167/546 | < Previous Page | 163 164 165 166 167 168 169 170 171 172 173 174  | Next Page >

  • Looking for Kiosk-style / camera store easy photo memory card to CD/DVD burning program for Windows-7 Notebook? For non techie user.

    - by Rob
    I'm looking for a Kiosk-style / camera shop easy photo memory card to CD/DVD burning program? For non technie user. The kind of system you see in a camera shop / store, e.g. in the UK, Jessops and Boots stores. This is for my Dad who is adept at general PC usage as a notebook owner, but would prefer something fairly simple. The task of burning photos to CD/DVD, in their original photo file .jpg form, i.e. NOT as CD or DVD video or slideshow, is what I'm looking for. I'm guessing this might be possible in Picasa, but all the options available might be superfluous and confusing. He could probably learn to use that but thought I would try simpler options first. Looking for something that guides the user through the steps/stages of the process, 'Wizard' style. Any suggestions? Platform: HP Windows 7 Home notebook with CD/DVD burner and SD memory card slot.

    Read the article

  • Agile Development

    - by James Oloo Onyango
    Alot of literature has and is being written about agile developement and its surrounding philosophies. In my quest to find the best way to express the importance of agile methodologies, i have found Robert C. Martin's "A Satire Of Two Companies" to be both the most concise and thorough! Enjoy the read! Rufus Inc Project Kick Off Your name is Bob. The date is January 3, 2001, and your head still aches from the recent millennial revelry. You are sitting in a conference room with several managers and a group of your peers. You are a project team leader. Your boss is there, and he has brought along all of his team leaders. His boss called the meeting. "We have a new project to develop," says your boss's boss. Call him BB. The points in his hair are so long that they scrape the ceiling. Your boss's points are just starting to grow, but he eagerly awaits the day when he can leave Brylcream stains on the acoustic tiles. BB describes the essence of the new market they have identified and the product they want to develop to exploit this market. "We must have this new project up and working by fourth quarter October 1," BB demands. "Nothing is of higher priority, so we are cancelling your current project." The reaction in the room is stunned silence. Months of work are simply going to be thrown away. Slowly, a murmur of objection begins to circulate around the conference table.   His points give off an evil green glow as BB meets the eyes of everyone in the room. One by one, that insidious stare reduces each attendee to quivering lumps of protoplasm. It is clear that he will brook no discussion on this matter. Once silence has been restored, BB says, "We need to begin immediately. How long will it take you to do the analysis?" You raise your hand. Your boss tries to stop you, but his spitwad misses you and you are unaware of his efforts.   "Sir, we can't tell you how long the analysis will take until we have some requirements." "The requirements document won't be ready for 3 or 4 weeks," BB says, his points vibrating with frustration. "So, pretend that you have the requirements in front of you now. How long will you require for analysis?" No one breathes. Everyone looks around to see whether anyone has some idea. "If analysis goes beyond April 1, we have a problem. Can you finish the analysis by then?" Your boss visibly gathers his courage: "We'll find a way, sir!" His points grow 3 mm, and your headache increases by two Tylenol. "Good." BB smiles. "Now, how long will it take to do the design?" "Sir," you say. Your boss visibly pales. He is clearly worried that his 3 mms are at risk. "Without an analysis, it will not be possible to tell you how long design will take." BB's expression shifts beyond austere.   "PRETEND you have the analysis already!" he says, while fixing you with his vacant, beady little eyes. "How long will it take you to do the design?" Two Tylenol are not going to cut it. Your boss, in a desperate attempt to save his new growth, babbles: "Well, sir, with only six months left to complete the project, design had better take no longer than 3 months."   "I'm glad you agree, Smithers!" BB says, beaming. Your boss relaxes. He knows his points are secure. After a while, he starts lightly humming the Brylcream jingle. BB continues, "So, analysis will be complete by April 1, design will be complete by July 1, and that gives you 3 months to implement the project. This meeting is an example of how well our new consensus and empowerment policies are working. Now, get out there and start working. I'll expect to see TQM plans and QIT assignments on my desk by next week. Oh, and don't forget that your crossfunctional team meetings and reports will be needed for next month's quality audit." "Forget the Tylenol," you think to yourself as you return to your cubicle. "I need bourbon."   Visibly excited, your boss comes over to you and says, "Gosh, what a great meeting. I think we're really going to do some world shaking with this project." You nod in agreement, too disgusted to do anything else. "Oh," your boss continues, "I almost forgot." He hands you a 30-page document. "Remember that the SEI is coming to do an evaluation next week. This is the evaluation guide. You need to read through it, memorize it, and then shred it. It tells you how to answer any questions that the SEI auditors ask you. It also tells you what parts of the building you are allowed to take them to and what parts to avoid. We are determined to be a CMM level 3 organization by June!"   You and your peers start working on the analysis of the new project. This is difficult because you have no requirements. But from the 10-minute introduction given by BB on that fateful morning, you have some idea of what the product is supposed to do.   Corporate process demands that you begin by creating a use case document. You and your team begin enumerating use cases and drawing oval and stick diagrams. Philosophical debates break out among the team members. There is disagreement as to whether certain use cases should be connected with <<extends>> or <<includes>> relationships. Competing models are created, but nobody knows how to evaluate them. The debate continues, effectively paralyzing progress.   After a week, somebody finds the iceberg.com Web site, which recommends disposing entirely of <<extends>> and <<includes>> and replacing them with <<precedes>> and <<uses>>. The documents on this Web site, authored by Don Sengroiux, describes a method known as stalwart-analysis, which claims to be a step-by-step method for translating use cases into design diagrams. More competing use case models are created using this new scheme, but again, people can't agree on how to evaluate them. The thrashing continues. More and more, the use case meetings are driven by emotion rather than by reason. If it weren't for the fact that you don't have requirements, you'd be pretty upset by the lack of progress you are making. The requirements document arrives on February 15. And then again on February 20, 25, and every week thereafter. Each new version contradicts the previous one. Clearly, the marketing folks who are writing the requirements, empowered though they might be, are not finding consensus.   At the same time, several new competing use case templates have been proposed by the various team members. Each template presents its own particularly creative way of delaying progress. The debates rage on. On March 1, Prudence Putrigence, the process proctor, succeeds in integrating all the competing use case forms and templates into a single, all-encompassing form. Just the blank form is 15 pages long. She has managed to include every field that appeared on all the competing templates. She also presents a 159- page document describing how to fill out the use case form. All current use cases must be rewritten according to the new standard.   You marvel to yourself that it now requires 15 pages of fill-in-the-blank and essay questions to answer the question: What should the system do when the user presses Return? The corporate process (authored by L. E. Ott, famed author of "Holistic Analysis: A Progressive Dialectic for Software Engineers") insists that you discover all primary use cases, 87 percent of all secondary use cases, and 36.274 percent of all tertiary use cases before you can complete analysis and enter the design phase. You have no idea what a tertiary use case is. So in an attempt to meet this requirement, you try to get your use case document reviewed by the marketing department, which you hope will know what a tertiary use case is.   Unfortunately, the marketing folks are too busy with sales support to talk to you. Indeed, since the project started, you have not been able to get a single meeting with marketing, which has provided a never-ending stream of changing and contradictory requirements documents.   While one team has been spinning endlessly on the use case document, another team has been working out the domain model. Endless variations of UML documents are pouring out of this team. Every week, the model is reworked.   The team members can't decide whether to use <<interfaces>> or <<types>> in the model. A huge disagreement has been raging on the proper syntax and application of OCL. Others on the team just got back from a 5-day class on catabolism, and have been producing incredibly detailed and arcane diagrams that nobody else can fathom.   On March 27, with one week to go before analysis is to be complete, you have produced a sea of documents and diagrams but are no closer to a cogent analysis of the problem than you were on January 3. **** And then, a miracle happens.   **** On Saturday, April 1, you check your e-mail from home. You see a memo from your boss to BB. It states unequivocally that you are done with the analysis! You phone your boss and complain. "How could you have told BB that we were done with the analysis?" "Have you looked at a calendar lately?" he responds. "It's April 1!" The irony of that date does not escape you. "But we have so much more to think about. So much more to analyze! We haven't even decided whether to use <<extends>> or <<precedes>>!" "Where is your evidence that you are not done?" inquires your boss, impatiently. "Whaaa . . . ." But he cuts you off. "Analysis can go on forever; it has to be stopped at some point. And since this is the date it was scheduled to stop, it has been stopped. Now, on Monday, I want you to gather up all existing analysis materials and put them into a public folder. Release that folder to Prudence so that she can log it in the CM system by Monday afternoon. Then get busy and start designing."   As you hang up the phone, you begin to consider the benefits of keeping a bottle of bourbon in your bottom desk drawer. They threw a party to celebrate the on-time completion of the analysis phase. BB gave a colon-stirring speech on empowerment. And your boss, another 3 mm taller, congratulated his team on the incredible show of unity and teamwork. Finally, the CIO takes the stage to tell everyone that the SEI audit went very well and to thank everyone for studying and shredding the evaluation guides that were passed out. Level 3 now seems assured and will be awarded by June. (Scuttlebutt has it that managers at the level of BB and above are to receive significant bonuses once the SEI awards level 3.)   As the weeks flow by, you and your team work on the design of the system. Of course, you find that the analysis that the design is supposedly based on is flawedno, useless; no, worse than useless. But when you tell your boss that you need to go back and work some more on the analysis to shore up its weaker sections, he simply states, "The analysis phase is over. The only allowable activity is design. Now get back to it."   So, you and your team hack the design as best you can, unsure of whether the requirements have been properly analyzed. Of course, it really doesn't matter much, since the requirements document is still thrashing with weekly revisions, and the marketing department still refuses to meet with you.     The design is a nightmare. Your boss recently misread a book named The Finish Line in which the author, Mark DeThomaso, blithely suggested that design documents should be taken down to code-level detail. "If we are going to be working at that level of detail," you ask, "why don't we simply write the code instead?" "Because then you wouldn't be designing, of course. And the only allowable activity in the design phase is design!" "Besides," he continues, "we have just purchased a companywide license for Dandelion! This tool enables 'Round the Horn Engineering!' You are to transfer all design diagrams into this tool. It will automatically generate our code for us! It will also keep the design diagrams in sync with the code!" Your boss hands you a brightly colored shrinkwrapped box containing the Dandelion distribution. You accept it numbly and shuffle off to your cubicle. Twelve hours, eight crashes, one disk reformatting, and eight shots of 151 later, you finally have the tool installed on your server. You consider the week your team will lose while attending Dandelion training. Then you smile and think, "Any week I'm not here is a good week." Design diagram after design diagram is created by your team. Dandelion makes it very difficult to draw these diagrams. There are dozens and dozens of deeply nested dialog boxes with funny text fields and check boxes that must all be filled in correctly. And then there's the problem of moving classes between packages. At first, these diagram are driven from the use cases. But the requirements are changing so often that the use cases rapidly become meaningless. Debates rage about whether VISITOR or DECORATOR design patterns should be used. One developer refuses to use VISITOR in any form, claiming that it's not a properly object-oriented construct. Someone refuses to use multiple inheritance, since it is the spawn of the devil. Review meetings rapidly degenerate into debates about the meaning of object orientation, the definition of analysis versus design, or when to use aggregation versus association. Midway through the design cycle, the marketing folks announce that they have rethought the focus of the system. Their new requirements document is completely restructured. They have eliminated several major feature areas and replaced them with feature areas that they anticipate customer surveys will show to be more appropriate. You tell your boss that these changes mean that you need to reanalyze and redesign much of the system. But he says, "The analysis phase is system. But he says, "The analysis phase is over. The only allowable activity is design. Now get back to it."   You suggest that it might be better to create a simple prototype to show to the marketing folks and even some potential customers. But your boss says, "The analysis phase is over. The only allowable activity is design. Now get back to it." Hack, hack, hack, hack. You try to create some kind of a design document that might reflect the new requirements documents. However, the revolution of the requirements has not caused them to stop thrashing. Indeed, if anything, the wild oscillations of the requirements document have only increased in frequency and amplitude.   You slog your way through them.   On June 15, the Dandelion database gets corrupted. Apparently, the corruption has been progressive. Small errors in the DB accumulated over the months into bigger and bigger errors. Eventually, the CASE tool just stopped working. Of course, the slowly encroaching corruption is present on all the backups. Calls to the Dandelion technical support line go unanswered for several days. Finally, you receive a brief e-mail from Dandelion, informing you that this is a known problem and that the solution is to purchase the new version, which they promise will be ready some time next quarter, and then reenter all the diagrams by hand.   ****   Then, on July 1 another miracle happens! You are done with the design!   Rather than go to your boss and complain, you stock your middle desk drawer with some vodka.   **** They threw a party to celebrate the on-time completion of the design phase and their graduation to CMM level 3. This time, you find BB's speech so stirring that you have to use the restroom before it begins. New banners and plaques are all over your workplace. They show pictures of eagles and mountain climbers, and they talk about teamwork and empowerment. They read better after a few scotches. That reminds you that you need to clear out your file cabinet to make room for the brandy. You and your team begin to code. But you rapidly discover that the design is lacking in some significant areas. Actually, it's lacking any significance at all. You convene a design session in one of the conference rooms to try to work through some of the nastier problems. But your boss catches you at it and disbands the meeting, saying, "The design phase is over. The only allowable activity is coding. Now get back to it."   ****   The code generated by Dandelion is really hideous. It turns out that you and your team were using association and aggregation the wrong way, after all. All the generated code has to be edited to correct these flaws. Editing this code is extremely difficult because it has been instrumented with ugly comment blocks that have special syntax that Dandelion needs in order to keep the diagrams in sync with the code. If you accidentally alter one of these comments, the diagrams will be regenerated incorrectly. It turns out that "Round the Horn Engineering" requires an awful lot of effort. The more you try to keep the code compatible with Dandelion, the more errors Dandelion generates. In the end, you give up and decide to keep the diagrams up to date manually. A second later, you decide that there's no point in keeping the diagrams up to date at all. Besides, who has time?   Your boss hires a consultant to build tools to count the number of lines of code that are being produced. He puts a big thermometer graph on the wall with the number 1,000,000 on the top. Every day, he extends the red line to show how many lines have been added. Three days after the thermometer appears on the wall, your boss stops you in the hall. "That graph isn't growing quickly enough. We need to have a million lines done by October 1." "We aren't even sh-sh-sure that the proshect will require a m-million linezh," you blather. "We have to have a million lines done by October 1," your boss reiterates. His points have grown again, and the Grecian formula he uses on them creates an aura of authority and competence. "Are you sure your comment blocks are big enough?" Then, in a flash of managerial insight, he says, "I have it! I want you to institute a new policy among the engineers. No line of code is to be longer than 20 characters. Any such line must be split into two or more preferably more. All existing code needs to be reworked to this standard. That'll get our line count up!"   You decide not to tell him that this will require two unscheduled work months. You decide not to tell him anything at all. You decide that intravenous injections of pure ethanol are the only solution. You make the appropriate arrangements. Hack, hack, hack, and hack. You and your team madly code away. By August 1, your boss, frowning at the thermometer on the wall, institutes a mandatory 50-hour workweek.   Hack, hack, hack, and hack. By September 1st, the thermometer is at 1.2 million lines and your boss asks you to write a report describing why you exceeded the coding budget by 20 percent. He institutes mandatory Saturdays and demands that the project be brought back down to a million lines. You start a campaign of remerging lines. Hack, hack, hack, and hack. Tempers are flaring; people are quitting; QA is raining trouble reports down on you. Customers are demanding installation and user manuals; salespeople are demanding advance demonstrations for special customers; the requirements document is still thrashing, the marketing folks are complaining that the product isn't anything like they specified, and the liquor store won't accept your credit card anymore. Something has to give.    On September 15, BB calls a meeting. As he enters the room, his points are emitting clouds of steam. When he speaks, the bass overtones of his carefully manicured voice cause the pit of your stomach to roll over. "The QA manager has told me that this project has less than 50 percent of the required features implemented. He has also informed me that the system crashes all the time, yields wrong results, and is hideously slow. He has also complained that he cannot keep up with the continuous train of daily releases, each more buggy than the last!" He stops for a few seconds, visibly trying to compose himself. "The QA manager estimates that, at this rate of development, we won't be able to ship the product until December!" Actually, you think it's more like March, but you don't say anything. "December!" BB roars with such derision that people duck their heads as though he were pointing an assault rifle at them. "December is absolutely out of the question. Team leaders, I want new estimates on my desk in the morning. I am hereby mandating 65-hour work weeks until this project is complete. And it better be complete by November 1."   As he leaves the conference room, he is heard to mutter: "Empowermentbah!" * * * Your boss is bald; his points are mounted on BB's wall. The fluorescent lights reflecting off his pate momentarily dazzle you. "Do you have anything to drink?" he asks. Having just finished your last bottle of Boone's Farm, you pull a bottle of Thunderbird from your bookshelf and pour it into his coffee mug. "What's it going to take to get this project done? " he asks. "We need to freeze the requirements, analyze them, design them, and then implement them," you say callously. "By November 1?" your boss exclaims incredulously. "No way! Just get back to coding the damned thing." He storms out, scratching his vacant head.   A few days later, you find that your boss has been transferred to the corporate research division. Turnover has skyrocketed. Customers, informed at the last minute that their orders cannot be fulfilled on time, have begun to cancel their orders. Marketing is re-evaluating whether this product aligns with the overall goals of the company. Memos fly, heads roll, policies change, and things are, overall, pretty grim. Finally, by March, after far too many sixty-five hour weeks, a very shaky version of the software is ready. In the field, bug-discovery rates are high, and the technical support staff are at their wits' end, trying to cope with the complaints and demands of the irate customers. Nobody is happy.   In April, BB decides to buy his way out of the problem by licensing a product produced by Rupert Industries and redistributing it. The customers are mollified, the marketing folks are smug, and you are laid off.     Rupert Industries: Project Alpha   Your name is Robert. The date is January 3, 2001. The quiet hours spent with your family this holiday have left you refreshed and ready for work. You are sitting in a conference room with your team of professionals. The manager of the division called the meeting. "We have some ideas for a new project," says the division manager. Call him Russ. He is a high-strung British chap with more energy than a fusion reactor. He is ambitious and driven but understands the value of a team. Russ describes the essence of the new market opportunity the company has identified and introduces you to Jane, the marketing manager, who is responsible for defining the products that will address it. Addressing you, Jane says, "We'd like to start defining our first product offering as soon as possible. When can you and your team meet with me?" You reply, "We'll be done with the current iteration of our project this Friday. We can spare a few hours for you between now and then. After that, we'll take a few people from the team and dedicate them to you. We'll begin hiring their replacements and the new people for your team immediately." "Great," says Russ, "but I want you to understand that it is critical that we have something to exhibit at the trade show coming up this July. If we can't be there with something significant, we'll lose the opportunity."   "I understand," you reply. "I don't yet know what it is that you have in mind, but I'm sure we can have something by July. I just can't tell you what that something will be right now. In any case, you and Jane are going to have complete control over what we developers do, so you can rest assured that by July, you'll have the most important things that can be accomplished in that time ready to exhibit."   Russ nods in satisfaction. He knows how this works. Your team has always kept him advised and allowed him to steer their development. He has the utmost confidence that your team will work on the most important things first and will produce a high-quality product.   * * *   "So, Robert," says Jane at their first meeting, "How does your team feel about being split up?" "We'll miss working with each other," you answer, "but some of us were getting pretty tired of that last project and are looking forward to a change. So, what are you people cooking up?" Jane beams. "You know how much trouble our customers currently have . . ." And she spends a half hour or so describing the problem and possible solution. "OK, wait a second" you respond. "I need to be clear about this." And so you and Jane talk about how this system might work. Some of her ideas aren't fully formed. You suggest possible solutions. She likes some of them. You continue discussing.   During the discussion, as each new topic is addressed, Jane writes user story cards. Each card represents something that the new system has to do. The cards accumulate on the table and are spread out in front of you. Both you and Jane point at them, pick them up, and make notes on them as you discuss the stories. The cards are powerful mnemonic devices that you can use to represent complex ideas that are barely formed.   At the end of the meeting, you say, "OK, I've got a general idea of what you want. I'm going to talk to the team about it. I imagine they'll want to run some experiments with various database structures and presentation formats. Next time we meet, it'll be as a group, and we'll start identifying the most important features of the system."   A week later, your nascent team meets with Jane. They spread the existing user story cards out on the table and begin to get into some of the details of the system. The meeting is very dynamic. Jane presents the stories in the order of their importance. There is much discussion about each one. The developers are concerned about keeping the stories small enough to estimate and test. So they continually ask Jane to split one story into several smaller stories. Jane is concerned that each story have a clear business value and priority, so as she splits them, she makes sure that this stays true.   The stories accumulate on the table. Jane writes them, but the developers make notes on them as needed. Nobody tries to capture everything that is said; the cards are not meant to capture everything but are simply reminders of the conversation.   As the developers become more comfortable with the stories, they begin writing estimates on them. These estimates are crude and budgetary, but they give Jane an idea of what the story will cost.   At the end of the meeting, it is clear that many more stories could be discussed. It is also clear that the most important stories have been addressed and that they represent several months worth of work. Jane closes the meeting by taking the cards with her and promising to have a proposal for the first release in the morning.   * * *   The next morning, you reconvene the meeting. Jane chooses five cards and places them on the table. "According to your estimates, these cards represent about one perfect team-week's worth of work. The last iteration of the previous project managed to get one perfect team-week done in 3 real weeks. If we can get these five stories done in 3 weeks, we'll be able to demonstrate them to Russ. That will make him feel very comfortable about our progress." Jane is pushing it. The sheepish look on her face lets you know that she knows it too. You reply, "Jane, this is a new team, working on a new project. It's a bit presumptuous to expect that our velocity will be the same as the previous team's. However, I met with the team yesterday afternoon, and we all agreed that our initial velocity should, in fact, be set to one perfectweek for every 3 real-weeks. So you've lucked out on this one." "Just remember," you continue, "that the story estimates and the story velocity are very tentative at this point. We'll learn more when we plan the iteration and even more when we implement it."   Jane looks over her glasses at you as if to say "Who's the boss around here, anyway?" and then smiles and says, "Yeah, don't worry. I know the drill by now."Jane then puts 15 more cards on the table. She says, "If we can get all these cards done by the end of March, we can turn the system over to our beta test customers. And we'll get good feedback from them."   You reply, "OK, so we've got our first iteration defined, and we have the stories for the next three iterations after that. These four iterations will make our first release."   "So," says Jane, can you really do these five stories in the next 3 weeks?" "I don't know for sure, Jane," you reply. "Let's break them down into tasks and see what we get."   So Jane, you, and your team spend the next several hours taking each of the five stories that Jane chose for the first iteration and breaking them down into small tasks. The developers quickly realize that some of the tasks can be shared between stories and that other tasks have commonalities that can probably be taken advantage of. It is clear that potential designs are popping into the developers' heads. From time to time, they form little discussion knots and scribble UML diagrams on some cards.   Soon, the whiteboard is filled with the tasks that, once completed, will implement the five stories for this iteration. You start the sign-up process by saying, "OK, let's sign up for these tasks." "I'll take the initial database generation." Says Pete. "That's what I did on the last project, and this doesn't look very different. I estimate it at two of my perfect workdays." "OK, well, then, I'll take the login screen," says Joe. "Aw, darn," says Elaine, the junior member of the team, "I've never done a GUI, and kinda wanted to try that one."   "Ah, the impatience of youth," Joe says sagely, with a wink in your direction. "You can assist me with it, young Jedi." To Jane: "I think it'll take me about three of my perfect workdays."   One by one, the developers sign up for tasks and estimate them in terms of their own perfect workdays. Both you and Jane know that it is best to let the developers volunteer for tasks than to assign the tasks to them. You also know full well that you daren't challenge any of the developers' estimates. You know these people, and you trust them. You know that they are going to do the very best they can.   The developers know that they can't sign up for more perfect workdays than they finished in the last iteration they worked on. Once each developer has filled his or her schedule for the iteration, they stop signing up for tasks.   Eventually, all the developers have stopped signing up for tasks. But, of course, tasks are still left on the board.   "I was worried that that might happen," you say, "OK, there's only one thing to do, Jane. We've got too much to do in this iteration. What stories or tasks can we remove?" Jane sighs. She knows that this is the only option. Working overtime at the beginning of a project is insane, and projects where she's tried it have not fared well.   So Jane starts to remove the least-important functionality. "Well, we really don't need the login screen just yet. We can simply start the system in the logged-in state." "Rats!" cries Elaine. "I really wanted to do that." "Patience, grasshopper." says Joe. "Those who wait for the bees to leave the hive will not have lips too swollen to relish the honey." Elaine looks confused. Everyone looks confused. "So . . .," Jane continues, "I think we can also do away with . . ." And so, bit by bit, the list of tasks shrinks. Developers who lose a task sign up for one of the remaining ones.   The negotiation is not painless. Several times, Jane exhibits obvious frustration and impatience. Once, when tensions are especially high, Elaine volunteers, "I'll work extra hard to make up some of the missing time." You are about to correct her when, fortunately, Joe looks her in the eye and says, "When once you proceed down the dark path, forever will it dominate your destiny."   In the end, an iteration acceptable to Jane is reached. It's not what Jane wanted. Indeed, it is significantly less. But it's something the team feels that can be achieved in the next 3 weeks.   And, after all, it still addresses the most important things that Jane wanted in the iteration. "So, Jane," you say when things had quieted down a bit, "when can we expect acceptance tests from you?" Jane sighs. This is the other side of the coin. For every story the development team implements,   Jane must supply a suite of acceptance tests that prove that it works. And the team needs these long before the end of the iteration, since they will certainly point out differences in the way Jane and the developers imagine the system's behaviour.   "I'll get you some example test scripts today," Jane promises. "I'll add to them every day after that. You'll have the entire suite by the middle of the iteration."   * * *   The iteration begins on Monday morning with a flurry of Class, Responsibilities, Collaborators sessions. By midmorning, all the developers have assembled into pairs and are rapidly coding away. "And now, my young apprentice," Joe says to Elaine, "you shall learn the mysteries of test-first design!"   "Wow, that sounds pretty rad," Elaine replies. "How do you do it?" Joe beams. It's clear that he has been anticipating this moment. "OK, what does the code do right now?" "Huh?" replied Elaine, "It doesn't do anything at all; there is no code."   "So, consider our task; can you think of something the code should do?" "Sure," Elaine said with youthful assurance, "First, it should connect to the database." "And thereupon, what must needs be required to connecteth the database?" "You sure talk weird," laughed Elaine. "I think we'd have to get the database object from some registry and call the Connect() method. "Ah, astute young wizard. Thou perceives correctly that we requireth an object within which we can cacheth the database object." "Is 'cacheth' really a word?" "It is when I say it! So, what test can we write that we know the database registry should pass?" Elaine sighs. She knows she'll just have to play along. "We should be able to create a database object and pass it to the registry in a Store() method. And then we should be able to pull it out of the registry with a Get() method and make sure it's the same object." "Oh, well said, my prepubescent sprite!" "Hay!" "So, now, let's write a test function that proves your case." "But shouldn't we write the database object and registry object first?" "Ah, you've much to learn, my young impatient one. Just write the test first." "But it won't even compile!" "Are you sure? What if it did?" "Uh . . ." "Just write the test, Elaine. Trust me." And so Joe, Elaine, and all the other developers began to code their tasks, one test case at a time. The room in which they worked was abuzz with the conversations between the pairs. The murmur was punctuated by an occasional high five when a pair managed to finish a task or a difficult test case.   As development proceeded, the developers changed partners once or twice a day. Each developer got to see what all the others were doing, and so knowledge of the code spread generally throughout the team.   Whenever a pair finished something significant whether a whole task or simply an important part of a task they integrated what they had with the rest of the system. Thus, the code base grew daily, and integration difficulties were minimized.   The developers communicated with Jane on a daily basis. They'd go to her whenever they had a question about the functionality of the system or the interpretation of an acceptance test case.   Jane, good as her word, supplied the team with a steady stream of acceptance test scripts. The team read these carefully and thereby gained a much better understanding of what Jane expected the system to do. By the beginning of the second week, there was enough functionality to demonstrate to Jane. She watched eagerly as the demonstration passed test case after test case. "This is really cool," Jane said as the demonstration finally ended. "But this doesn't seem like one-third of the tasks. Is your velocity slower than anticipated?"   You grimace. You'd been waiting for a good time to mention this to Jane but now she was forcing the issue. "Yes, unfortunately, we are going more slowly than we had expected. The new application server we are using is turning out to be a pain to configure. Also, it takes forever to reboot, and we have to reboot it whenever we make even the slightest change to its configuration."   Jane eyes you with suspicion. The stress of last Monday's negotiations had still not entirely dissipated. She says, "And what does this mean to our schedule? We can't slip it again, we just can't. Russ will have a fit! He'll haul us all into the woodshed and ream us some new ones."   You look Jane right in the eyes. There's no pleasant way to give someone news like this. So you just blurt out, "Look, if things keep going like they're going, we're not going to be done with everything by next Friday. Now it's possible that we'll figure out a way to go faster. But, frankly, I wouldn't depend on that. You should start thinking about one or two tasks that could be removed from the iteration without ruining the demonstration for Russ. Come hell or high water, we are going to give that demonstration on Friday, and I don't think you want us to choose which tasks to omit."   "Aw forchrisakes!" Jane barely manages to stifle yelling that last word as she stalks away, shaking her head. Not for the first time, you say to yourself, "Nobody ever promised me project management would be easy." You are pretty sure it won't be the last time, either.   Actually, things went a bit better than you had hoped. The team did, in fact, have to drop one task from the iteration, but Jane had chosen wisely, and the demonstration for Russ went without a hitch. Russ was not impressed with the progress, but neither was he dismayed. He simply said, "This is pretty good. But remember, we have to be able to demonstrate this system at the trade show in July, and at this rate, it doesn't look like you'll have all that much to show." Jane, whose attitude had improved dramatically with the completion of the iteration, responded to Russ by saying, "Russ, this team is working hard, and well. When July comes around, I am confident that we'll have something significant to demonstrate. It won't be everything, and some of it may be smoke and mirrors, but we'll have something."   Painful though the last iteration was, it had calibrated your velocity numbers. The next iteration went much better. Not because your team got more done than in the last iteration but simply because the team didn't have to remove any tasks or stories in the middle of the iteration.   By the start of the fourth iteration, a natural rhythm has been established. Jane, you, and the team know exactly what to expect from one another. The team is running hard, but the pace is sustainable. You are confident that the team can keep up this pace for a year or more.   The number of surprises in the schedule diminishes to near zero; however, the number of surprises in the requirements does not. Jane and Russ frequently look over the growing system and make recommendations or changes to the existing functionality. But all parties realize that these changes take time and must be scheduled. So the changes do not cause anyone's expectations to be violated. In March, there is a major demonstration of the system to the board of directors. The system is very limited and is not yet in a form good enough to take to the trade show, but progress is steady, and the board is reasonably impressed.   The second release goes even more smoothly than the first. By now, the team has figured out a way to automate Jane's acceptance test scripts. The team has also refactored the design of the system to the point that it is really easy to add new features and change old ones. The second release was done by the end of June and was taken to the trade show. It had less in it than Jane and Russ would have liked, but it did demonstrate the most important features of the system. Although customers at the trade show noticed that certain features were missing, they were very impressed overall. You, Russ, and Jane all returned from the trade show with smiles on your faces. You all felt as though this project was a winner.   Indeed, many months later, you are contacted by Rufus Inc. That company had been working on a system like this for its internal operations. Rufus has canceled the development of that system after a death-march project and is negotiating to license your technology for its environment.   Indeed, things are looking up!

    Read the article

  • Windows Azure Evolution &ndash; Caching (Preview)

    - by Shaun
    Caching is a popular topic when we are building a high performance and high scalable system not only on top of the cloud platform but the on-premise environment as well. On March 2011 the Windows Azure AppFabric Caching had been production launched. It provides an in-memory, distributed caching service over the cloud. And now, in this June 2012 update, the cache team announce a grand new caching solution on Windows Azure, which is called Windows Azure Caching (Preview). And the original Windows Azure AppFabric Caching was renamed to Windows Azure Shared Caching.   What’s Caching (Preview) If you had been using the Shared Caching you should know that it is constructed by a bunch of cache servers. And when you want to use you should firstly create a cache account from the developer portal and specify the size you want to use, which means how much memory you can use to store your data that wanted to be cached. Then you can add, get and remove them through your code through the cache URL. The Shared Caching is a multi-tenancy system which host all cached items across all users. So you don’t know which server your data was located. This caching mode works well and can take most of the cases. But it has some problems. The first one is the performance. Since the Shared Caching is a multi-tenancy system, which means all cache operations should go through the Shared Caching gateway and then routed to the server which have the data your are looking for. Even though there are some caches in the Shared Caching system it also takes time from your cloud services to the cache service. Secondary, the Shared Caching service works as a block box to the developer. The only thing we know is my cache endpoint, and that’s all. Someone may satisfied since they don’t want to care about anything underlying. But if you need to know more and want more control that’s impossible in the Shared Caching. The last problem would be the price and cost-efficiency. You pay the bill based on how much cache you requested per month. But when we host a web role or worker role, it seldom consumes all of the memory and CPU in the virtual machine (service instance). If using Shared Caching we have to pay for the cache service while waste of some of our memory and CPU locally. Since the issues above Microsoft offered a new caching mode over to us, which is the Caching (Preview). Instead of having a separated cache service, the Caching (Preview) leverage the memory and CPU in our cloud services (web role and worker role) as the cache clusters. Hence the Caching (Preview) runs on the virtual machines which hosted or near our cloud applications. Without any gateway and routing, since it located in the same data center and same racks, it provides really high performance than the Shared Caching. The Caching (Preview) works side-by-side to our application, initialized and worked as a Windows Service running in the virtual machines invoked by the startup tasks from our roles, we could get more information and control to them. And since the Caching (Preview) utilizes the memory and CPU from our existing cloud services, so it’s free. What we need to pay is the original computing price. And the resource on each machines could be used more efficiently.   Enable Caching (Preview) It’s very simple to enable the Caching (Preview) in a cloud service. Let’s create a new windows azure cloud project from Visual Studio and added an ASP.NET Web Role. Then open the role setting and select the Caching page. This is where we enable and configure the Caching (Preview) on a role. To enable the Caching (Preview) just open the “Enable Caching (Preview Release)” check box. And then we need to specify which mode of the caching clusters we want to use. There are two kinds of caching mode, co-located and dedicate. The co-located mode means we use the memory in the instances we run our cloud services (web role or worker role). By using this mode we must specify how many percentage of the memory will be used as the cache. The default value is 30%. So make sure it will not affect the role business execution. The dedicate mode will use all memory in the virtual machine as the cache. In fact it will reserve some for operation system, azure hosting etc.. But it will try to use as much as the available memory to be the cache. As you can see, the Caching (Preview) was defined based on roles, which means all instances of this role will apply the same setting and play as a whole cache pool, and you can consume it by specifying the name of the role, which I will demonstrate later. And in a windows azure project we can have more than one role have the Caching (Preview) enabled. Then we will have more caches. For example, let’s say I have a web role and worker role. The web role I specified 30% co-located caching and the worker role I specified dedicated caching. If I have 3 instances of my web role and 2 instances of my worker role, then I will have two caches. As the figure above, cache 1 was contributed by three web role instances while cache 2 was contributed by 2 worker role instances. Then we can add items into cache 1 and retrieve it from web role code and worker role code. But the items stored in cache 1 cannot be retrieved from cache 2 since they are isolated. Back to our Visual Studio we specify 30% of co-located cache and use the local storage emulator to store the cache cluster runtime status. Then at the bottom we can specify the named caches. Now we just use the default one. Now we had enabled the Caching (Preview) in our web role settings. Next, let’s have a look on how to consume our cache.   Consume Caching (Preview) The Caching (Preview) can only be consumed by the roles in the same cloud services. As I mentioned earlier, a cache contributed by web role can be connected from a worker role if they are in the same cloud service. But you cannot consume a Caching (Preview) from other cloud services. This is different from the Shared Caching. The Shared Caching is opened to all services if it has the connection URL and authentication token. To consume the Caching (Preview) we need to add some references into our project as well as some configuration in the Web.config. NuGet makes our life easy. Right click on our web role project and select “Manage NuGet packages”, and then search the package named “WindowsAzure.Caching”. In the package list install the “Windows Azure Caching Preview”. It will download all necessary references from the NuGet repository and update our Web.config as well. Open the Web.config of our web role and find the “dataCacheClients” node. Under this node we can specify the cache clients we are going to use. For each cache client it will use the role name to identity and find the cache. Since we only have this web role with the Caching (Preview) enabled so I pasted the current role name in the configuration. Then, in the default page I will add some code to show how to use the cache. I will have a textbox on the page where user can input his or her name, then press a button to generate the email address for him/her. And in backend code I will check if this name had been added in cache. If yes I will return the email back immediately. Otherwise, I will sleep the tread for 2 seconds to simulate the latency, then add it into cache and return back to the page. 1: protected void btnGenerate_Click(object sender, EventArgs e) 2: { 3: // check if name is specified 4: var name = txtName.Text; 5: if (string.IsNullOrWhiteSpace(name)) 6: { 7: lblResult.Text = "Error. Please specify name."; 8: return; 9: } 10:  11: bool cached; 12: var sw = new Stopwatch(); 13: sw.Start(); 14:  15: // create the cache factory and cache 16: var factory = new DataCacheFactory(); 17: var cache = factory.GetDefaultCache(); 18:  19: // check if the name specified is in cache 20: var email = cache.Get(name) as string; 21: if (email != null) 22: { 23: cached = true; 24: sw.Stop(); 25: } 26: else 27: { 28: cached = false; 29: // simulate the letancy 30: Thread.Sleep(2000); 31: email = string.Format("{0}@igt.com", name); 32: // add to cache 33: cache.Add(name, email); 34: } 35:  36: sw.Stop(); 37: lblResult.Text = string.Format( 38: "Cached = {0}. Duration: {1}s. {2} => {3}", 39: cached, sw.Elapsed.TotalSeconds.ToString("0.00"), name, email); 40: } The Caching (Preview) can be used on the local emulator so we just F5. The first time I entered my name it will take about 2 seconds to get the email back to me since it was not in the cache. But if we re-enter my name it will be back at once from the cache. Since the Caching (Preview) is distributed across all instances of the role, so we can scaling-out it by scaling-out our web role. Just use 2 instances and tweak some code to show the current instance ID in the page, and have another try. Then we can see the cache can be retrieved even though it was added by another instance.   Consume Caching (Preview) Across Roles As I mentioned, the Caching (Preview) can be consumed by all other roles within the same cloud service. For example, let’s add another web role in our cloud solution and add the same code in its default page. In the Web.config we add the cache client to one enabled in the last role, by specifying its role name here. Then we start the solution locally and go to web role 1, specify the name and let it generate the email to us. Since there’s no cache for this name so it will take about 2 seconds but will save the email into cache. And then we go to web role 2 and specify the same name. Then you can see it retrieve the email saved by the web role 1 and returned back very quickly. Finally then we can upload our application to Windows Azure and test again. Make sure you had changed the cache cluster status storage account to the real azure account.   More Awesome Features As a in-memory distributed caching solution, the Caching (Preview) has some fancy features I would like to highlight here. The first one is the high availability support. This is the first time I have heard that a distributed cache support high availability. In the distributed cache world if a cache cluster was failed, the data it stored will be lost. This behavior was introduced by Memcached and is followed by almost all distributed cache productions. But Caching (Preview) provides high availability, which means you can specify if the named cache will be backup automatically. If yes then the data belongs to this named cache will be replicated on another role instance of this role. Then if one of the instance was failed the data can be retrieved from its backup instance. To enable the backup just open the Caching page in Visual Studio. In the named cache you want to enable backup, change the Backup Copies value from 0 to 1. The value of Backup Copies only for 0 and 1. “0” means no backup and no high availability while “1” means enabled high availability with backup the data into another instance. But by using the high availability feature there are something we need to make sure. Firstly the high availability does NOT means the data in cache will never be lost for any kind of failure. For example, if we have a role with cache enabled that has 10 instances, and 9 of them was failed, then most of the cached data will be lost since the primary and backup instance may failed together. But normally is will not be happened since MS guarantees that it will use the instance in the different fault domain for backup cache. Another one is that, enabling the backup means you store two copies of your data. For example if you think 100MB memory is OK for cache, but you need at least 200MB if you enabled backup. Besides the high availability, the Caching (Preview) support more features introduced in Windows Server AppFabric Caching than the Windows Azure Shared Caching. It supports local cache with notification. It also support absolute and slide window expiration types as well. And the Caching (Preview) also support the Memcached protocol as well. This means if you have an application based on Memcached, you can use Caching (Preview) without any code changes. What you need to do is to change the configuration of how you connect to the cache. Similar as the Windows Azure Shared Caching, MS also offers the out-of-box ASP.NET session provider and output cache provide on top of the Caching (Preview).   Summary Caching is very important component when we building a cloud-based application. In the June 2012 update MS provides a new cache solution named Caching (Preview). Different from the existing Windows Azure Shared Caching, Caching (Preview) runs the cache cluster within the role instances we have deployed to the cloud. It gives more control, more performance and more cost-effect. So now we have two caching solutions in Windows Azure, the Shared Caching and Caching (Preview). If you need a central cache service which can be used by many cloud services and web sites, then you have to use the Shared Caching. But if you only need a fast, near distributed cache, then you’d better use Caching (Preview).   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

    Read the article

  • Why is my Android app camera preview running out of memory on my AVD?

    - by Bryan
    I have yet to try this on an actual device, but expect similar results. Anyway, long story short, whenever I run my app on the emulator, it crashes due to an out of memory exception. My code really is essentially the same as the camera preview API demo from google, which runs perfectly fine. The only file in the app (that I created/use) is as below- package berbst.musicReader; import java.io.IOException; import android.app.Activity; import android.content.Context; import android.hardware.Camera; import android.os.Bundle; import android.view.SurfaceHolder; import android.view.SurfaceView; /********************************* * Music Reader v.0001 * Still VERY under construction. * @author Bryan * *********************************/ public class MusicReader extends Activity { private MainScreen main; @Override //Begin activity public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); main = new MainScreen(this); setContentView(main); } class MainScreen extends SurfaceView implements SurfaceHolder.Callback { SurfaceHolder sHolder; Camera cam; MainScreen(Context context) { super(context); //Set up SurfaceHolder sHolder = getHolder(); sHolder.addCallback(this); sHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); } public void surfaceCreated(SurfaceHolder holder) { // Open the camera and start viewing cam = Camera.open(); try { cam.setPreviewDisplay(holder); } catch (IOException exception) { cam.release(); cam = null; } } public void surfaceDestroyed(SurfaceHolder holder) { // Kill all our crap with the surface cam.stopPreview(); cam.release(); cam = null; } public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { // Modify parameters to match size. Camera.Parameters params = cam.getParameters(); params.setPreviewSize(w, h); cam.setParameters(params); cam.startPreview(); } } }

    Read the article

  • C: Proper syntax for allocating memory using pointers to pointers.

    - by ~kero-05h
    This is my first time posting here, hopefully I will not make a fool of myself. I am trying to use a function to allocate memory to a pointer, copy text to the buffer, and then change a character. I keep getting a segfault and have tried looking up the answer, my syntax is probably wrong, I could use some enlightenment. /* My objective is to pass a buffer to my Copy function, allocate room, and copy text to it. Then I want to modify the text and print it.*/ #include <stdio.h> #include <stdlib.h> #include <string.h> int Copy(char **Buffer, char *Text); int main() { char *Text = malloc(sizeof(char) * 100); char *Buffer; strncpy(Text, "1234567890\n", 100); Copy(&Buffer, Text); } int Copy(char **Buffer, char *Text) { int count; count = strlen(Text)+1; *Buffer = malloc(sizeof(char) * count); strncpy(*Buffer, Text, 5); *Buffer[2] = 'A'; /* This results in a segfault. "*Buffer[1] = 'A';" results in no differece in the output. */ printf("%s\n", *Buffer); }

    Read the article

  • Write to memory buffer instead of file with libjpeg?

    - by Richard Knop
    I have found this function which uses libjpeg to write to a file: int write_jpeg_file( char *filename ) { struct jpeg_compress_struct cinfo; struct jpeg_error_mgr jerr; /* this is a pointer to one row of image data */ JSAMPROW row_pointer[1]; FILE *outfile = fopen( filename, "wb" ); if ( !outfile ) { printf("Error opening output jpeg file %s\n!", filename ); return -1; } cinfo.err = jpeg_std_error( &jerr ); jpeg_create_compress(&cinfo); jpeg_stdio_dest(&cinfo, outfile); /* Setting the parameters of the output file here */ cinfo.image_width = width; cinfo.image_height = height; cinfo.input_components = bytes_per_pixel; cinfo.in_color_space = color_space; /* default compression parameters, we shouldn't be worried about these */ jpeg_set_defaults( &cinfo ); /* Now do the compression .. */ jpeg_start_compress( &cinfo, TRUE ); /* like reading a file, this time write one row at a time */ while( cinfo.next_scanline < cinfo.image_height ) { row_pointer[0] = &raw_image[ cinfo.next_scanline * cinfo.image_width * cinfo.input_components]; jpeg_write_scanlines( &cinfo, row_pointer, 1 ); } /* similar to read file, clean up after we're done compressing */ jpeg_finish_compress( &cinfo ); jpeg_destroy_compress( &cinfo ); fclose( outfile ); /* success code is 1! */ return 1; } I would actually need to write the jpeg compressed image just to memory buffer, without saving it to a file, to save time. Could somebody give me an example how to do it? I have been searching the web for a while but the documentation is very rare if any and examples are also difficult to come by.

    Read the article

  • How to create view model without sorting collections in memory.

    - by Chevex
    I have a view model (below). public class TopicsViewModel { public Topic Topic { get; set; } public Reply LastReply { get; set; } } I want to populate an IQueryable<TopicsViewModel> with values from my IQueryable<Topic> collection and IQueryable<Reply> collection. I do not want to use the attached entity collection (i.e. Topic.Replies) because I only want the last reply for that topic and doing Topic.Replies.Last() loads the entire entity collection in memory and then grabs the last one in the list. I am trying to stay in IQueryable so that the query is executed in the database. I also don't want to foreach through topics and query replyRepository.Replies because looping through IQueryable<Topic> will start the lazy loading. I'd prefer to build one expression and have all the leg work done in the lower layers. I have the following: IQueryable<TopicsViewModel> topicsViewModel = from x in topicRepository.Topics from y in replyRepository.Replies where y.TopicID == x.TopicID orderby y.PostedDate ascending select new TopicsViewModel { Topic = x, LastReply = y }; But this isn't working. Any ideas how I can populate an IQueryable or IEnumerable of TopicsViewModel so that it queries the database and grabs topics and that topic's last reply? I am trying really hard to avoid grabbing all replies related to that topic. I only want to grab the last reply. Thank you for any insight you have to offer.

    Read the article

  • Nginx , Apache , Mysql , Memcache with server 4G ram. How optimize to enoigh of memory?

    - by TomSawyer
    i have 1 dedicated server with Nginx proxy for Apache. Memcache, mysql, 4G Ram. These day, my visitor on my site wasn't increased, but my server get overload always in some specified time. (9AM - 15PM) Ram in use is increased second by second to full. that's moment, my server will get overload. i have to kill all apache , mysql service and reboot it to get free memory. and it'll full again. that's the terrible circle. here is my ram in use at the moment 160(nginx) 220(apache) 512(memcache) 924(mysql) here's process number 4(nginx) 14(apache) 5(memcache) 20(mysql) and here's my my.cnf config. someone can help me to optimize it? [mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock user=mysql skip-locking skip-networking skip-name-resolve # enable log-slow-queries log-slow-queries = /var/log/mysql-slow-queries.log long_query_time=3 max_connections=200 wait_timeout=64 connect_timeout = 10 interactive_timeout = 25 thread_stack = 512K max_allowed_packet=16M table_cache=1500 read_buffer_size=4M join_buffer_size=4M sort_buffer_size=4M read_rnd_buffer_size = 4M max_heap_table_size=256M tmp_table_size=256M thread_cache=256 query_cache_type=1 query_cache_limit=4M query_cache_size=16M thread_concurrency=8 myisam_sort_buffer_size=128M # Disabling symbolic-links is recommended to prevent assorted security risks symbolic-links=0 [mysqldump] quick max_allowed_packet=16M [mysql] no-auto-rehash [isamchk] key_buffer=256M sort_buffer=256M read_buffer=64M write_buffer=64M [myisamchk] key_buffer=256M sort_buffer=256M read_buffer=64M write_buffer=64M [mysqlhotcopy] interactive-timeout [mysql.server] user=mysql basedir=/var/lib [mysqld_safe] log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid

    Read the article

  • Inline function v. Macro in C -- What's the Overhead (Memory/Speed)?

    - by Jason R. Mick
    I searched Stack Overflow for the pros/cons of function-like macros v. inline functions. I found the following discussion: Pros and Cons of Different macro function / inline methods in C ...but it didn't answer my primary burning question. Namely, what is the overhead in c of using a macro function (with variables, possibly other function calls) v. an inline function, in terms of memory usage and execution speed? Are there any compiler-dependent differences in overhead? I have both icc and gcc at my disposal. My code snippet I'm modularizing is: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = AttractiveTerm * AttractiveTerm; EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); My reason for turning it into an inline function/macro is so I can drop it into a c file and then conditionally compile other similar, but slightly different functions/macros. e.g.: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = pow(SigmaSquared/RadialDistanceSquared,9); EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); (note the difference in the second line...) This function is a central one to my code and gets called thousands of times per step in my program and my program performs millions of steps. Thus I want to have the LEAST overhead possible, hence why I'm wasting time worrying about the overhead of inlining v. transforming the code into a macro. Based on the prior discussion I already realize other pros/cons (type independence and resulting errors from that) of macros... but what I want to know most, and don't currently know is the PERFORMANCE. I know some of you C veterans will have some great insight for me!!

    Read the article

  • How to cast C struct just another struct type if their memory size are equal?

    - by Eonil
    I have 2 matrix structs means equal data but have different form like these: // Matrix type 1. typedef float Scalar; typedef struct { Scalar e[4]; } Vector; typedef struct { Vector e[4]; } Matrix; // Matrix type 2 (you may know this if you're iPhone developer) struct CATransform3D { CGFloat m11, m12, m13, m14; CGFloat m21, m22, m23, m24; CGFloat m31, m32, m33, m34; CGFloat m41, m42, m43, m44; }; typedef struct CATransform3D CATransform3D; Their memory size are equal. So I believe there is a way to convert these types without any pointer operations or copy like this: // Implemented from external lib. CATransform3D CATransform3DMakeScale (CGFloat sx, CGFloat sy, CGFloat sz); Matrix m = (Matrix)CATransform3DMakeScale ( 1, 2, 3 ); Is this possible? Currently compiler prints an "error: conversion to non-scalar type requested" message.

    Read the article

  • Ruby - Nokogiri - Parsing XML from memory and putting all same name node values into an array.

    - by r3nrut
    I have an XML I'm trying to parse from memory and get the status of each of my heart beat tests using Nokogiri. Here is the solution I have... xml = <a:HBeat> <a:ElapsedTime>3 ms</a:ElapsedTime> <a:Name>Service 1</a:Name> <a:Status>true</a:Status> </a:HBeat> <a:HBeat> <a:ElapsedTime>4 ms</a:ElapsedTime> <a:Name>Service 2</a:Name> <a:Status>true</a:Status> </a:HBeat> <a:HBeat> I have tried using both css and xpath to pull back the value for each Status and put it into an array. Code is below: doc = Nokogiri::XML.parse(xml) #service_state = doc.css("a:HBeat, a:Status", 'a' => 'http://schemas.datacontract.org/2004/07/OpenAPI.Entity').map {|node| node.children.text} service_state = doc.xpath("//*[@a:Status]", 'a' => 'http://schemas.datacontract.org/2004/07/OpenAPI.Entity').map(&:text) Both will return service_state = []. Any thoughts or recommendations? Also, consider that I have almost identical xml for another test and I used the following snippet of code which does exactly what I wanted but for some reason isn't working with the xml that contains namespaces. service_state = doc.css("HBeat Status").map(&:text) Thanks!

    Read the article

  • How to draw a part of a window into a memory device context?

    - by Nell
    I'm using simple statements to keep it, er, simple: The screen goes from 0, 0 to 1000, 1000 (screen coordinates). A window goes from 100, 100 to 900, 900 (screen coordinates). I have a memory device context that goes from 0, 0 to 200, 200 (logical coordinates). I need to send a WM_PRINT message to the window. I can pass the device context to the window via WM_PRINT, but I cannot pass which part of its window it should draw into the device context. Is there some way to alter the device context that will result in the window drawing a specific part of itself into the device context (say, its bottom right portion from 700, 700 to 900, 900)? (This is all under plain old GDI and in C or C++. Any solution must be too.) Please note: This problem is part of a larger solution in which the device context size is fixed and speed is crucial, so I cannot draw the window in full into a separate device context and blit the part I want from the resultant full bitmap into my device context.

    Read the article

  • Faster or more memory-efficient solution in Python for this Codejam problem.

    - by jeroen.vangoey
    I tried my hand at this Google Codejam Africa problem (the contest is already finished, I just did it to improve my programming skills). The Problem: You are hosting a party with G guests and notice that there is an odd number of guests! When planning the party you deliberately invited only couples and gave each couple a unique number C on their invitation. You would like to single out whoever came alone by asking all of the guests for their invitation numbers. The Input: The first line of input gives the number of cases, N. N test cases follow. For each test case there will be: One line containing the value G the number of guests. One line containing a space-separated list of G integers. Each integer C indicates the invitation code of a guest. Output For each test case, output one line containing "Case #x: " followed by the number C of the guest who is alone. The Limits: 1 = N = 50 0 < C = 2147483647 Small dataset 3 = G < 100 Large dataset 3 = G < 1000 Sample Input: 3 3 1 2147483647 2147483647 5 3 4 7 4 3 5 2 10 2 10 5 Sample Output: Case #1: 1 Case #2: 7 Case #3: 5 This is the solution that I came up with: with open('A-large-practice.in') as f: lines = f.readlines() with open('A-large-practice.out', 'w') as output: N = int(lines[0]) for testcase, i in enumerate(range(1,2*N,2)): G = int(lines[i]) for guest in range(G): codes = map(int, lines[i+1].split(' ')) alone = (c for c in codes if codes.count(c)==1) output.write("Case #%d: %d\n" % (testcase+1, alone.next())) It runs in 12 seconds on my machine with the large input. Now, my question is, can this solution be improved in Python to run in a shorter time or use less memory? The analysis of the problem gives some pointers on how to do this in Java and C++ but I can't translate those solutions back to Python.

    Read the article

  • How to use strtok in C properly so there is no memory leak?

    - by user246392
    I am somewhat confused by what happens when you call strtok on a char pointer in C. I know that it modifies the contents of the string, so if I call strtok on a variable named 'line', its content will change. Assume I follow the bellow approach: void function myFunc(char* line) { // get a pointer to the original memory block char* garbageLine = line; // Do some work // Call strtok on 'line' multiple times until it returns NULL // Do more work free(garbageLine); } Further assume that 'line' is malloced before it is passed to myFunc. Am I supposed to free the original string after using strtok or does it do the job for us? Also, what happens if 'line' is not malloced and I attempt to use the function above? Is it safer to do the following instead? (Assume the programmer won't call free if he knows the line is not malloced) Invocation char* garbageLine = line; myFunc(line); free(garbageLine); Function definition void function myFunc(char* line) { // Do some work // Call strtok on 'line' multiple times until it returns NULL // Do more work }

    Read the article

  • How to increase video memory in libvirt/KVM gui?

    - by Dejan
    In the 'Virtual Hardware details', it lists the model as 'cirrus' with 9MB of RAM. The RAM field cannot be changed, but how to increate the video RAM? My host OS is RH6 and gust OS is Fedora16. EDIT: From guest OS, when I run xvinfo it displays 'no adaptors present'. I was trying to play a video using gstreamers xvimagesink plugin (XFree86 video output plugin using Xv extension). The problem is that xvimagesink is using hardware acceleration for video performance and hence the error Could not initialize Xv output. I guess I'll have to configure hardware acceleration for the guest.

    Read the article

  • macbook pro for developer

    - by Michael Ellick Ang
    Which of the following choices would be more beneficial to developers ? 13 inch Macbook Pro, Core 2 Duo, 4 GB Memory, 128 GB SSD - $1550 - Faster Storage 13 inch Macbook Pro, Core 2 Duo, 8 GB Memory, 250 GB HD - $1600 - More Memory 15 inch Macbook Pro, Core i5, 4 GB Memory, 320 GB HD - $1800 - Better CPU Thanks.

    Read the article

  • IPMI sdr entity 8 (memory module) only showing 3 records?

    - by thinice
    I've got two Dell PE R710's - A has a single socket and 3 DIMMs in one bank B has both sockets and 6 (2 banks @ 3 DIMMs) filled The output from "ipmitool sdr entity 8" confuses me - according to the OpenIPMI documentation these are supposed to represent DIMM slots. Output from A (1 CPU, 3 DIMMS, 1 bank.): ~#: ipmitool sdr entity 8 Temp | 0Ah | ok | 8.1 | 27 degrees C Temp | 0Bh | ns | 8.1 | Disabled Temp | 0Ch | ucr | 8.1 | 52 degrees C Output from B (2 CPUs, 3 DIMMS in both banks, 6 total): ~#: ipmitool sdr entity 8 Temp | 0Ah | ok | 8.1 | 26 degrees C Temp | 0Bh | ok | 8.1 | 25 degrees C Temp | 0Ch | ucr | 8.1 | 51 degrees C Now, I'm starting to think this output isn't DIMMS themselves, but maybe a sensor for each bank and something else? (Otherwise, shouldn't I see 6 readings for the one with both banks active?) The CPU's aren't near 50 deg C, so I doubt the significantly higher reading is due to proximity - Is anyone able to explain what I'm seeing? Does the output from my ipmitool sdr entity 8 -v here on pastebin seem to hint at different sensors? The sensor naming conventions are poor - seems like a dell thing. Here is output from racadm racdump

    Read the article

  • dmidecode showing more ram slots than available?

    - by Jestep
    I have some failing RAM in a server and I ran dmidecode to figure out what tyoe of RAM I needed to replace it with. The server has 6 RAM slots, 4 of which are in use. When I run dmidecode this is what I get. dmidecode 2.10 SMBIOS 2.4 present. Handle 0x001F, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: 72 bits Data Width: 64 bits Size: 2048 MB Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 00 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0020, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: 72 bits Data Width: 64 bits Size: 2048 MB Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 01 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0021, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: Unknown Data Width: Unknown Size: No Module Installed Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 02 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0022, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: Unknown Data Width: Unknown Size: No Module Installed Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 03 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0023, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: 72 bits Data Width: 64 bits Size: 2048 MB Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 10 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0024, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: 72 bits Data Width: 64 bits Size: 2048 MB Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 11 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0025, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: Unknown Data Width: Unknown Size: No Module Installed Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 12 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Handle 0x0026, DMI type 17, 27 bytes Memory Device Array Handle: 0x001E Error Information Handle: No Error Total Width: Unknown Data Width: Unknown Size: No Module Installed Form Factor: DIMM Set: 1 Locator: JXXX Bank Locator: DIMM 13 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Does anyone know why it would show 8 slots, with 4 empty instead of 6 slots with 2 empty? Also, but my records and by other tools, the server has 16Gb and not 8Gb in it currently. grep MemTotal /proc/meminfo MemTotal: 16435808 kB The board is a Tyan S5372-LC, running CentOS 5.4 x64. Also, my error log is showing errors in bank 6. Is there any way to determine which slot bank 6 is in via: dmidecode?

    Read the article

  • Why is my new Phenom II 965 BE not significantly faster than my old Athlon 64 X2 4600+?

    - by Software Monkey
    I recently rebuilt my 5 year old computer. I upgraded all core components, in particular from an Athlon 64 X2 4600+ at 2.4 GHz with DDR2 800 to a Phenom II 965 BE (quad core) at 3.6 GHz with DDR3 1333 (actually 1600, but testing consistently detected memory errors at 1600). The motherboard is also much newer and better. The HDD's (x3), DVD writer and card reader are the same. The BIOS memory config is auto-everything except the base timing which I overrode to 1T instead of 2T. The BIOS CPU multiplier is slightly over-clocked to 3.6 GHz from the stock 3.4 GHz. I noticed compiling Java is slower than I expected. As it happens I have some (single-threaded) Java pattern-matching code which is CPU and memory bound and for which I have performance numbers recorded on a number of hardware platforms, including my old system. So I did a test run on the new equipment and was stunned to find that the numbers are only slightly better than my old system, about 25%. The data set it is operating on is a 148,975 character array, which should easily fit in caches, but in any event the new CPU has larger caches all around. The system was, of course, otherwise idle for the test and the test run is a timed 10 seconds to eliminate scheduling anomalies. A long while ago, when I upgraded only memory from DD2 667 to DDR2 800 there was no change in performance of this test, which subjectively supports that the test cycle does not need to (significantly) access main memory, but yes it is creating and garbage collecting a large number of objects in the process of this test (low millions of matches are found for the pattern set). I am about 99.999% certain the code hasn't changed since I last ran it on 2009-03-17 - but I can't easily retest the old hardware, because it is currently in pieces on my work-bench waiting to be built into a new computer for my kids. Note that Windows (XP) reports a CPU speed of 795 MHz unless I have some thing running. With stuff running it seems to jump all over the place each time I use ALT-Pause to display the system properties, everywhere from 795 MHz to 3.4 Ghz. So why might my shiny new hardware under-performing so badly? EDIT: The old memory was Mushkin DDR2 800 with timings set for auto which should have been 5-5-5-12. The new memory is Corsair DDR3 1600, running at 1333 with timings also auto which are 9-9-9-21. In both cases they are a paired set of dual channel DIMMs. I was waiting to ensure my system was stable before tweaking with memory timings.

    Read the article

  • USB Virus, "Program too big to fit in memory"?

    - by ApprenticeHacker
    I got an installer for a piece of software via usb from a friend.Now what was weird was that although my friend and I had the same OS, same brand of laptop and I had a newer version (though I don't think this quite matters), the installer was running properly for him but not for me. It just showed a command line window and exited. I ran it via a batch file in which I included "pause" after running it. Here's the screenshot: Later my friend called me and told me that it was the USB that was the problem. It had some kind of virus on it and it corrupted every executable or folder on it , and it renamed all the sub_files inside folders to some weird jargon. He had tried using another USB and the installer worked fine. Now the friend has (unfortunately) gone back to his city and I can't get the installer again from him. My question is: Is there any way to repair the installer executable and run it? and Do you think the virus has infected my PC? (I have run a system scan with my antivirus and it showed nothing but still I'm worried)

    Read the article

  • "The program is too big to fit in memory" problem?!!

    - by user47038
    Please help me!!! This is most amazing error that i have ever had, we write 100 CD, in these CDs we got one setup.exe file that autorun. in some of these CDs when I explore the cd the setup.exe file become the command prompt file and give me above error. and when I reset the system and put it in another pc it`s ok. if I reset the first pc the autorun.exe run. so I change it different computer, randomly get this problem. I am sure about the virus, because I checked on different pcs and with fully update definition so someone tell me what happen?

    Read the article

  • Computer suddenly dies; screen displays weird flickering lines, then restarts

    - by Imray
    I've been having this terrible problem for a little while and just managed to get a picture of 'dead screen' for the first time and I am posting it to seek help. Randomly, at irregular intervals (typically once a week), while working on something (it's been different things every time) my computer will just suddenly go dead - the screen turns to exactly the picture below (the lines flicker a little bit), it hangs there for a few seconds and then restarts. Obviously this is extremely frustrating and I want to try to stop it. I've searched numerous postings with similar keywords but nothing exactly the same as mine. Does anyone have any idea what might be the cause of this? I would post all my system settings and installed programs but the list is long and I don't know how much relevance each item would be. If you'd like to know something specific, please comment and I'll let you know whatever you need. SPECS C:\Users\Imray>systeminfo Host Name: Imray OS Name: Microsoft Windows 7 Professional OS Version: 6.1.7600 N/A Build 7600 OS Manufacturer: Microsoft Corporation OS Configuration: Standalone Workstation OS Build Type: Multiprocessor Free Registered Owner: Imray - Owner Registered Organization: Product ID: 00371-152-9333854-85895 Original Install Date: 06/09/1999, 5:45:21 PM System Boot Time: 22/03/2013, 8:58:18 AM System Manufacturer: Gateway System Model: DX4840 System Type: x64-based PC Processor(s): 1 Processor(s) Installed. [01]: Intel64 Family 6 Model 37 Stepping 2 GenuineIntel ~3201 Mhz BIOS Version: American Megatrends Inc. P01-A3 , 17/05/2010 Windows Directory: C:\Windows System Directory: C:\Windows\system32 Boot Device: \Device\HarddiskVolume2 System Locale: en-us;English (United States) Input Locale: en-us;English (United States) Time Zone: (UTC-05:00) Eastern Time (US & Canada) Total Physical Memory: 6,135 MB Available Physical Memory: 3,632 MB Virtual Memory: Max Size: 12,268 MB Virtual Memory: Available: 8,114 MB Virtual Memory: In Use: 4,154 MB Page File Location(s): C:\pagefile.sys Domain: WORKGROUP Logon Server: \\Imray-OWNER Hotfix(s): 4 Hotfix(s) Installed. [01]: KB971033 [02]: KB958559 [03]: KB977206 [04]: KB981889 Network Card(s): 2 NIC(s) Installed. [01]: 802.11n Wireless PCI Express Card LAN Adapter Connection Name: Wireless Network Connection DHCP Enabled: Yes DHCP Server: 192.168.2.1 IP address(es) [01]: 192.168.2.13 [02]: fe80::1df1:5399:6890:91f6 [02]: Microsoft Virtual WiFi Miniport Adapter Connection Name: Wireless Network Connection 2 DHCP Enabled: Yes DHCP Server: N/A IP address(es) Graphics Card Specs Name ATI Radeon HD 5570 PNP Device ID PCI\VEN_1002&DEV_68D9&SUBSYS_E142174B&REV_00\4&18A4B35E&0&0008 Adapter Type ATI display adapter (0x68D9), ATI Technologies Inc. compatible Adapter Description ATI Radeon HD 5570 Adapter RAM 1.00 GB (1,073,741,824 bytes) Installed Drivers atiu9p64 aticfx64 aticfx64 atiu9pag aticfx32 aticfx32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64 Driver Version 8.700.0.0 INF File oem1.inf (ati2mtag_Evergreen section) Color Planes Not Available Color Table Entries 4294967296 Resolution 1920 x 1080 x 59 hertz Bits/Pixel 32 Memory Address 0xD0000000-0xDFFFFFFF Memory Address 0xFBDE0000-0xFBDFFFFF I/O Port 0x0000D000-0x0000DFFF IRQ Channel IRQ 4294967293 I/O Port 0x000003B0-0x000003BB I/O Port 0x000003C0-0x000003DF Memory Address 0xA0000-0xBFFFF Driver c:\windows\system32\drivers\atikmpag.sys (8.14.1.6095, 181.00 KB (185,344 bytes), 06/09/1999 5:59 PM)

    Read the article

  • How does data I/O takes place on USB Flash Memory ?

    - by user35704
    I want to know how is data I/O takes place on flash drives which are typically EEPROM's . I thought so as I was writing a C Program that involves file handling . For a normal HDD , that would involve returning the file pointer and reading or writing data to the disk which would be done by read/write HEAD . While in EEPROM's there is no read/write head , as it's works on mnemonic commands , So how come does the C file handling program works when I apply it to a file on flash drive ?

    Read the article

< Previous Page | 163 164 165 166 167 168 169 170 171 172 173 174  | Next Page >