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  • I write barely functional scripts that tend to not be resuable and make the baby jesus cry. Please h

    - by maxxpower
    I received a request to add around 100 users to a linux box the users are already in ldap so I can't just use newusers and point it at a text file. Another admin is taking care of the ldap piece so all I have to do is create all the home directories and chown them to the correct user once he adds the users to the box. creating the directories isn't a problem, but I'd like a more elegant script for chowning them to the correct user. what I have currently basically looks like chown -R testuser1 testgroup1 /home/tetsuser1; chown -R testuser2 testgroup2 /home/testgroup2; chown -R testsuser3 testgroup1 /home/testuser3 bascially I took the request that the user name and group name popped it into excel added a column of "chown -R" to the front, then added a column of "/", copied and pasted the username column after it and then added a column of ";" and dragged it down to the second to last row. Popped it into notepad ran some quick find and replaces and in less than a minute I have a completed request and a sad empty feeling. I know this was a really ghetto method and I'm trying to get away from using excel to avoid learning new scripting techniques so here's my real question. tl;dr I made 100 home directories and chowned them to the correct users, but it was ugly. Actual question below. You have a file named idlist that looks like this (only with say 1000 users and real usernames and groups) testuser1 testgroup1 testuser2 testgroup2 testuser3 testgroup1 write a script that creates home directories for all the users and chowns the created directories to the correct user and group. To make the directories I used the following(feel free to flame/correct me on this as well. ) var= 'cut -f1 -d" " idlist' (I used backticks not apostrophes around the cut command) mkdir $var

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  • Is Perl's flip-flop operator bugged? It has global state, how can I reset it?

    - by Evan Carroll
    I'm dismayed. Ok, so this was probably the most fun perl bug I've ever found. Even today I'm learning new stuff about perl. Essentially, the flip-flop operator .. which returns false until the left-hand-side returns true, and then true until the right-hand-side returns false keep global state (or that is what I assume.) My question is can I reset it, (perhaps this would be a good addition to perl4-esque hardly ever used reset())? Or, is there no way to use this operator safely? I also don't see this (the global context bit) documented anywhere in perldoc perlop is this a mistake? Code use feature ':5.10'; use strict; use warnings; sub search { my $arr = shift; grep { !( /start/ .. /never_exist/ ) } @$arr; } my @foo = qw/foo bar start baz end quz quz/; my @bar = qw/foo bar start baz end quz quz/; say 'first shot - foo'; say for search \@foo; say 'second shot - bar'; say for search \@bar; Spoiler $ perl test.pl first shot foo bar second shot

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  • positioning text/image with a border

    - by user167487
    Learning html/css, having trouble with positioning text and or images within a border on a page exactly where i want them. I'm first trying to stack them underneath each other vertically, but i dont know how to move each box underneath, at the moment they are stacking horizontally until they go over the max width, what do i do? HTML: <div id="column1"> <p>blah blah blah</p> </div> <div id="column2"> <p>blah blah blah</p> </div> <div id="column3"> <p>blah blah blah</p> </div> CSS: p { font-family: Tahoma; font-size: 14px; margin: 1px; padding: 10px; text-align: left; background-color: white; width: 800px; } #column1 {float: left; position: relative; width: 200px; padding: 3px; background: gray ; top: 10px;margin: 1px; } #column2 {float: left; position: relative; width: 200px; padding: 3px; background: orange; top:50px;margin: 1px; } #column3 {float: left; position: relative; width: 200px; padding: 3px; background: gray; top: 100px;margin: 1px; }

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  • Two objects with dependencies for each other. Is that bad?

    - by Kasper Grubbe
    Hi SO. I am learning a lot about design patterns these days. And I want to ask you about a design question that I can't find an answer to. Currently I am building a little Chat-server using sockets, with multiple Clients. Currently I have three classes. Person-class which holds information like nick, age and a Room-object. Room-class which holds information like room-name, topic and a list of Persons currently in that room. Hotel-class which have a list of Persons and a list of Rooms on the server. I have made a diagram to illustrate it (Sorry for the big size!): http://i.imgur.com/Kpq6V.png I have a list of players on the server in the Hotel-class because it would be nice to keep track of how many there are online right now (Without having to iterate through all of the rooms). The persons live in the Hotel-class because I would like to be able to search for a specific Person without searching the rooms. Is this bad design? Is there another way of achieve it? Thanks.

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  • Django Threaded Commenting System

    - by Yasin Ozel
    (and sorry for my english) I am learning Python and Django. Now, my challange is developing threaded generic comment system. There is two models, Post and Comment. -Post can be commented. -Comment can be commented. (endless/threaded) -Should not be a n+1 query problem in system. (No matter how many comments, should not increase the number of queries) My current models are like this: class Post(models.Model): title = models.CharField(max_length=100) content = models.TextField() child = generic.GenericRelation( 'Comment', content_type_field='parent_content_type', object_id_field='parent_object_id' ) class Comment(models.Model): content = models.TextField() child = generic.GenericRelation( 'self', content_type_field='parent_content_type', object_id_field='parent_object_id' ) parent_content_type = models.ForeignKey(ContentType) parent_object_id = models.PositiveIntegerField() parent = generic.GenericForeignKey( "parent_content_type", "parent_object_id") Are my models right? And how can i get all comment (with hierarchy) of post, without n+1 query problem? Note: I know mttp and other modules but I want to learn this system. Edit: I run "Post.objects.all().prefetch_related("child").get(pk=1)" command and this gave me post and its child comment. But when I wanna get child command of child command a new query is running. I can change command to ...prefetch_related("child__child__child...")... then still a new query running for every depth of child-parent relationship. Is there anyone who has idea about resolve this problem?

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  • slot function not getting called

    - by chappar
    I am learning QT and trying out some examples. I am trying to make a dialog that disappears a label when a button is pressed and makes it appear when the same button is pressed again. Below is the code. #include <QApplication> #include <QPushButton> #include <QLabel> #include <QDialog> #include <QObject> #include <QHBoxLayout> int main(int argc, char ** argv) { QApplication app(argc, argv); QDialog *dialog = new QDialog; QPushButton *testButton = new QPushButton(QObject::tr("test")); QLabel * testLabel = new QLabel (QObject::tr("test")); QHBoxLayout * layout = new QHBoxLayout; layout->addWidget(testButton); layout->addWidget(testLabel); QObject::connect(testButton, SIGNAL(toggled(bool)), testLabel, SLOT(setVisible(bool))); dialog->setLayout(layout); dialog->show(); return app.exec(); } It is not working. Whenever i press the test button nothing happens. But if i change the signal slot connections as QObject::connect(testButton, SIGNAL(clicked(bool)), testLabel, SLOT(setVisible(bool))); it makes the label disappear. So, why it is not working with signal "toggled". What i am guessing is, it is not able to find that signal. Can you guys throw some light?

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  • subtotals in columns usind reshape2 in R

    - by user1043144
    I have spent some time now learning RESHAPE2 and plyr but I still do not get it. This time I have a problem with (a) subtotals and (b) passing different aggregate functions . Here an example using data from the excellent tutorial on the blog of mrdwab http://news.mrdwab.com/ # libraries library(plyr) library(reshape2) # get data and add few more variables book.sales = read.csv("http://news.mrdwab.com/data-booksales") book.sales$Stock = book.sales$Quantity + 10 book.sales$SubjCat[(book.sales$Subject == 'Economics') | (book.sales$Subject == 'Management') ] <- '1_EconSciences' book.sales$SubjCat[book.sales$Subject %in% c('Anthropology', 'Politics', 'Sociology') ] <- '2_SocSciences' book.sales$SubjCat[book.sales$Subject %in% c('Communication', 'Fiction', 'History', 'Research', 'Statistics') ] <- '3_other' # to get to my starting dataframe (close to the project I am working on) book.sales1 <- ddply(book.sales, c('Region', 'Representative', 'SubjCat', 'Subject', 'Publisher'), summarize, Stock = sum(Stock), Sold = sum(Quantity), Ratio = round((100 * sum(Quantity)/ sum(Stock)), digits = 1)) #melt it m.book.sales = melt(data = book.sales1, id.vars = c('Region', 'Representative', 'SubjCat', 'Subject', 'Publisher'), measured.vars = c('Stock', 'Sold', 'Ratio')) # cast it Tab1 <- dcast(data = m.book.sales, formula = Region + Representative ~ Publisher + variable, fun.aggregate = sum, margins = c('Region', 'Representative')) Now my questions : I have been able to add the subtotals in rows. But is it possible also to add margins in the columns. Say for example, Totals of Stock for one Publisher ? Sorry I meant to say example total sold for all publishers There is a problem with the columns with “ratio”. How can I get “mean” instead of “sum” for this variable ? P.S: I have seen some examples using reshape. Will you recommend to use it instead of reshape2 (which seems not to include the functionalities of two functions).

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  • How to Manage CSS Explosion

    - by Jason
    I have been heavily relying on CSS for a website that I am working on (currently, everything is done as property values within each tag on the website and I'm trying to get away from that to make updates significantly easier). The problem I am running into, is I'm starting to get a bit of "CSS explosion" going on. It is becoming difficult for me to decide how to best organize and abstract data within the CSS file. For example: I am using a large number of div tags within the website (previously it was completely tables based). So I'm starting to get a lot of CSS that looks like this... div.title { background-color: Blue; color: White; text-align: center; } div.footer { /* Stuff Here */ } div.body { /* Stuff Here */ } etc. It's not too bad yet, but since I am learning here, I was wondering if recommendations could be made on how best to organize the various parts of a CSS file. What I don't want to get to is where I have a separate CSS attribute for every single thing on my website (which I have seen happen), and I always want the CSS file to be fairly intuitive. (P.S. I do realize this is a very generic, high-level question. My ultimate goal is to make it easy to use the CSS files and demonstrate their power to increase the speed of web development so other individuals that may work on this site in the future will also get into the practice of using them rather than hard-coding values everywhere.)

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  • "multiply frog enemy" timer and array AS3

    - by VideoDnd
    How can I use the counter value to multiply the frogs in the array? My counter goes from 0-100. I want to prove that I can increment the enemies using a counter. EXPLAINED BETTER I have 10 frogs in an array. I want to use a timer to add 10 more frogs on each iteration of the TimerEvent.TIMER firing. //currentCount var timer:Timer = new Timer(1000, 50); timer.addEventListener(TimerEvent.TIMER, countdown); timer.start(); function countdown(event:TimerEvent) { // myText.text = String(0 + timer.currentCount); } //Creates 10 enemies "I want enemies to multiply 0-100" var enemyArray:Array = new Array(); for (var i:int = 0; i < 10; i++) { var noname:FrogClass = new FrogClass(); noname.x = i*10; //this will just assign some different x and y value depending on i. noname.y = i*11; enemyArray.push(noname); //put the enemy into the array addChild(noname); //puts it on the stage } SYMBOL PROPERTIES NAME "noname" CLASS "FrogClass" WHY I need specific examples using strings and arrays, because I'm stuck in a learning curve. Stupid examples are more fun!

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  • How do I define a Calculated Measure in MDX based on a Dimension Attribute?

    - by ShaneD
    I would like to create a calculated measure that sums up only a specific subset of records in my fact table based on a dimension attribute. Given: Dimension Date LedgerLineItem {Charge, Payment, Write-Off, Copay, Credit} Measures LedgerAmount Relationships * LedgerLineItem is a degenerate dimension of FactLedger If I break down LedgerAmount by LedgerLineItem.Type I can easily see how much is charged, paid, credit, etc, but when I do not break it down by LedgerLineItem.Type I cannot easily add the credit, paid, credit, etc into a pivot table. I would like to create separate calculated measures that sum only specific type (or multiple types) of ledger facts. An example of the desired output would be: | Year | Charged | Total Paid | Amount - Ledger | | 2008 | $1000 | $600 | -$400 | | 2009 | $2000 | $1500 | -$500 | | Total | $3000 | $2100 | -$900 | I have tried to create the calculated measure a couple of ways and each one works in some circumstances but not in others. Now before anyone says do this in ETL, I have already done it in ETL and it works just fine. What I am trying to do as part of learning to understand MDX better is to figure out how to duplicate what I have done in the ETL in MDX as so far I am unable to do that. Here are two attempts I have made and the problems with them. This works only when ledger type is in the pivot table. It returns the correct amount of the ledger entries (although in this case it is identical to [amount - ledger] but when I try to remove type and just get the sum of all ledger entries it returns unknown. CASE WHEN ([Ledger].[Type].currentMember = [Ledger].[Type].&[Credit]) OR ([Ledger].[Type].currentMember = [Ledger].[Type].&[Paid]) OR ([Ledger].[Type].currentMember = [Ledger].[Type].&[Held Money: Copay]) THEN [Measures].[Amount - ledger] ELSE 0 END This works only when ledger type is not in the pivot table. It always returns the total payment amount, which is incorrect when I am slicing by type as I would only expect to see the credit portion under credit, the paid portion, under paid, $0 under charge, etc. sum({([Ledger].[Type].&[Credit]), ([Ledger].[Type].&[Paid]), ([Ledger].[Type].&[Held Money: Copay])}, [Measures].[Amount - ledger]) Is there any way to make this return the correct numbers regardless of whether Ledger.Type is included in my pivot table or not?

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  • Properties vs. Fields: Need help grasping the uses of Properties over Fields.

    - by pghtech
    First off, I have read through a list of postings on this topic and I don't feel I have grasped properties because of what I had come to understand about encapsulation and field modifiers (private, public..ect). One of the main aspects of C# that I have come to learn is the importance of data protection within your code by the use of encapsulation. I 'thought' I understood that to be because of the ability of the use of the modifiers (private, public, internal, protected). However, after learning about properties I am sort of torn in understanding not only properties uses, but the overall importance/ability of data protection (what I understood as encapsulation) within C#. To be more specific, everything I have read when I got to properties in C# is that you should try to use them in place of fields when you can because of: 1) they allow you to change the data type when you can't when directly accessing the field directly. 2) they add a level of protection to data access However, from what I 'thought' I had come to know about the use of field modifiers did #2, it seemed to me that properties just generated additional code unless you had some reason to change the type (#1) - because you are (more or less) creating hidden methods to access fields as opposed to directly. Then there is the whole modifiers being able to be added to Properties which further complicates my understanding for the need of properties to access data. I have read a number of chapters from different writers on "properties" and none have really explained a good understanding of properties vs. fields vs. encapsulation (and good programming methods). Can someone explain: 1) why I would want to use properties instead of fields (especially when it appears I am just adding additional code 2) any tips on recognizing the use of properties and not seeing them as simply methods (with the exception of the get;set being apparent) when tracing other peoples code? 3) Any general rules of thumb when it comes to good programming methods in relation to when to use what? Thanks and sorry for the long post - I didn't want to just ask a question that has been asked 100x without explaining why I am asking it again.

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  • Grails UrlMappings with .html

    - by Glennn
    I'm developing a Grails web application (mainly as a learning exercise). I have previously written some standard Grails apps, but in this case I wanted to try creating a controller that would intercept all requests (including static html) of the form: <a href="/testApp/testJsp.jsp">test 1</a> <a href="/testApp/testGsp.gsp">test 2</a> <a href="/testApp/testHtm.htm">test 3</a> <a href="/testApp/testHtml.html">test 4</a> The intent is to do some simple business logic (auditing) each time a user clicks a link. I know I could do this using a Filter (or a range of other methods), however I thought this should work too and wanted to do this using a Grails framework. I set up the Grail UrlMappings.groovy file to map all URLs of that form (/$myPathParam?) to a single controller: class UrlMappings { static mappings = { "/$controller/$action?/$id?"{ constraints { } } "/$path?" (controller: 'auditRecord', action: 'showPage') "500"(view:'/error') } } In that controller (in the appropriate "showPage" action) I've been printing out the path information, for example: def showPage = { println "params.path = " + params.path ... render(view: resultingView) } The results of the println in the showPage action for each of my four links are testJsp.jsp testGsp.gsp testHtm.htm testHtml Why is the last one "testHtml", not "testHtml.html"? In a previous (Stack Overflow query) Olexandr encountered this issue and was advised to simply concatenate the value of request.format - which, indeed, does return "html". However request.format also returns "html" for all four links. I'm interested in gaining an understanding of what Grails is doing and why. Is there some way to configure Grails so the params.path variable in the controller shows "testHtml.html" rather than stripping off the "html" extension? It doesn't seem to remove the extension for any other file type (including .htm). Is there a good reason it's doing this? I know that it is a bit unusual to use a controller for static html, but still would like to understand what's going on.

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  • Javascript hide/show classes with checkbox

    - by Christina
    I am just learning javascript, so please bear with me! I want to be able to use checkboxes to choose to hide/show div classes (to basically filter the amount of info being shown). It is done in this... but I'm try to figure out something much simpler (since I don't need to dynamically generate the checkbox options.) I came across this example: The Javascript: function showMe (it, box) { var vis = (box.checked) ? "block" : "none"; document.getElementById(it).style.display = vis; } The HTML <form> <input type="checkbox" checked="checked" value="value1" onclick="showMe('div1', this)" />value1 <input type="checkbox" checked="checked" value="value2" onclick="showMe('div2', this)" />value2 <input type="checkbox" checked="checked" value="value3" onclick="showMe('div3', this)" />value3 </form> <div id="div1" style="display:block">Show Div 1</div> <div id="div2" style="display:block">Show Div 2</div> <div id="div3" style="display:block">Show Div 3</div> </body> </html> But it only works for div ids, not classes. Any idea on how I can work this? Thanks in advance if you can help me out!

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  • What are the benefits of the PHP the different PHP compression libraries?

    - by Christopher W. Allen-Poole
    I've been looking into ways to compress PHP libraries, and I've found several libraries which might be useful, but I really don't know much about them. I've specifically been reading about bcompiler and PHAR libraries. Is there any performance benefit in either of these? Are there any "gotchas" I need to watch out for? What are the relative benefits? Do either of them add to/detract from performance? I'm also interested in learning of other libs which might be out there which are not obvious in the documentation? As an aside, does anyone happen to know whether these work more like zip files which just happen to have the code in there, or if they operate more like Python's pre-compiling which actually runs a pseudo-compiler? ======================= EDIT ======================= I've been asked, "What are you trying to accomplish?" Well, I suppose the answer is that this is all hypothetical. It is a combination of these: What if my pet project becomes the most popular web project on earth and I want to distribute it quickly and easily? (hay, a man can dream, right?) It also seems if using PHAR can be done easily, it would be the best way to create a subversion snapshot. Python has this really cool pre-compiling policy, I wonder if PHP has something like that? These libraries seem to do something similar. Will they do that? Hey, these libraries seem pretty neat, but I'd like clarification on the differences as they seem to do the same thing

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  • WPF DataBinding to standard CLR properties in code-behind

    - by nukefusion
    Hi everyone, Just learning WPF databinding and have a gap in my understanding. I've seen a few similar questions on StackOverflow, but I'm still struggling in determining what I have done wrong. I have a simple Person class with a Firstname and Surname property (standard CLR properties). I also have a standard CLR property on my Window class that exposes an instance of Person. I've then got some XAML, with two methods of binding. The first works, the second doesn't. Can anybody help me to understand why the second method fails? There's no binding error message in the Output log. <Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfApplication1" Title="Window1" Height="300" Width="300" DataContext="{Binding RelativeSource={RelativeSource Self}, Path=MyPerson}"> <StackPanel> <Label>My Person</Label> <WrapPanel> <Label>First Name:</Label> <Label Content="{Binding RelativeSource={RelativeSource AncestorType=Window, Mode=FindAncestor}, Path=MyPerson.FirstName}"></Label> </WrapPanel> <WrapPanel> <Label>Last Name:</Label> <Label Content="{Binding MyPerson.Surname}"></Label> </WrapPanel> </StackPanel> Edit: Ok, thanks so far. I've changed the second expression to: <Label Content="{Binding Surname}"></Label> I still can't get it to work though!

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  • Getting Started with Ruby & Ruby on Rails

    - by JakeTheSnake
    Some background: I'm a jack-of-all traits, one of which is programming. I learned VB6 through Excel and PHP for creating websites and so far it's worked out just fine for me. I'm not CS major or even mathematically inclined - logic is what interests me. Current status: I'm willing to learn new and more powerful languages; my first foray into such a route is learning Ruby. I went to the main Ruby website and did the interactive intro. (by the way, I'm currently getting redirected to google.com when I try the link...it's happening to other websites as well...is my computer infected?) I liked what I learned and wanted to get started using Ruby to create websites. I downloaded InstantRails and installed it; everything so far has been fine - the program starts up just fine, and I can test some Ruby code in the console. However my troubles begin when I try and view a web page with Ruby code present. Lastly, my problem: As in PHP, I can browse to the .php file directly and through using PHP tags and some simple 'echo' statements I can be on my way in making dynamic web pages. However with the InstantRails app working, accessing a .rb or .rhtml page doesn't produce similar results. I made a simple text file named 'test.rb' and put basic HTML tags in there (html, head, body) and the Ruby tags <%= and % with some ruby code inside. The web page actually shows the tags and the code - as if it's all just plain HTML. I take it Ruby isn't parsing the page before it is displayed to the user, but this is where my lack of understanding of the Ruby environment stops me short. Where do I go from here?

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  • Only last row in method execute (Objective-C)

    - by Emil
    First I want to apologize for my lack of knowledge in programming in general. I am in the way of learning and have discovered that this site is a huge compliment for me of doing so. I have created a program with three UITextField(thePlace,theVerb,theOutput) and two UITextView where one of the textviews(theOutput) take the text from the other textview(theTemplate) and replaces some strings with the text entered in the textfields. When I click a button it triggers the method createStory that is listed below. This works fine with one exception. The text in the output only changes the string 'number' to the text in the textfield. However if I change the order in the method to replace 'place','number','verb' only the verb is changed, not the number. Im sure this is some sort of easy fix but I can't find it. Can some of you help me with my troubleshooting? - (IBAction)createStory:(id)sender { theOutput.text=[theTemplate.text stringByReplacingOccurrencesOfString:@"<place>" withString:thePlace.text]; theOutput.text=[theTemplate.text stringByReplacingOccurrencesOfString:@"<verb>" withString:theVerb.text]; theOutput.text=[theTemplate.text stringByReplacingOccurrencesOfString:@"<number>" withString:theNumber.text]; } Many thanks // Emil

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  • Using pipes in Linux with C

    - by Dave
    Hi, I'm doing a course in Operating Systems and we're supposed to learn how to use pipes to transfer data between processes. We were given this simple piece of code which demonstrates how to use pipes,but I'm having difficulty understanding it. #include <stdio.h> #include <stdlib.h> #include <unistd.h> main() { int pipefd [2], n; char buff[100] ; if( pipe( pipefd) < 0) { printf("can not create pipe \n"); } printf("read fd = %d, write fd = %d \n", pipefd[0], pipefd[1]); if ( write (pipefd[1],"hello world\n", 12)!= 12) { printf("pipe write error \n"); } if( ( n = read ( pipefd[0] , buff, sizeof ( buff) ) ) <= 0 ) { printf("pipe read error \n"); } write ( 1, buff, n ) ; exit (0); } What does the write function do? It seems to send data to the pipe and also print it to the screen (at least it seems like the second time the write function is called it does this). Does anyone have any suggestions of good websites for learning about topics such as this, FIFO, signals, other basic linux commands used in C?

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  • Javascript for loop with variable

    - by Jascination
    I'm doing some simple javascript learning at the moment and I'm stuck on how to solve this problem. (the basic form comes from Code Academy). The task is to create 3 rabbit objects, each with a different adjective as an attribute. Then, print describeMyself() for each rabbit. Instead of repeating myself 3 times, I'd like to find a way to solve the problem with a for loop to make it more streamlined/challenging for myself. Here's what I tried: function Rabbit(adjective) { this.adjective = adjective; this.describeMyself = function() { console.log("I am a " + this.adjective + " rabbit"); }; } var rabbit1 = new Rabbit(fluffy); var rabbit2 = new Rabbit(happy); var rabbit3 = new Rabbit(sleepy); for (i=1; i<=3; i++){ ("rabbit"+i).describeMyself(); } Obviously, the ("rabbit"+i).describeMyself() is wrong. I want the loop to create "rabbit1", "rabbit2" and "rabbit3". What's the proper syntax here?

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  • DSP - Filtering frequencies using DFT

    - by Trap
    I'm trying to implement a DFT-based 8-band equalizer for the sole purpose of learning. To prove that my DFT implementation works I fed an audio signal, analyzed it and then resynthesized it again with no modifications made to the frequency spectrum. So far so good. I'm using the so-called 'standard way of calculating the DFT' which is by correlation. This method calculates the real and imaginary parts both N/2 + 1 samples in length. To attenuate a frequency I'm just doing: float atnFactor = 0.6; Re[k] *= atnFactor; Im[k] *= atnFactor; where 'k' is an index in the range 0 to N/2, but what I get after resynthesis is a slighty distorted signal, especially at low frequencies. The input signal sample rate is 44.1 khz and since I just want a 8-band equalizer I'm feeding the DFT 16 samples at a time so I have 8 frequency bins to play with. Can someone show me what I'm doing wrong? I tried to find info on this subject on the internet but couldn't find any. Thanks in advance.

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  • Anything speaking against the bitnami.org Ruby/Rails/Redmine Stack?

    - by Pekka
    I am looking to set up a Redmine server on a Windows virtual machine on my local workstation. (Background in this related question.) I have zero knowledge of Ruby nor Rails, and while Redmine may be the opportunity to dip into those platforms somewhat, my first goal is to get it running as quickly and easily as possible. For that, I am eyeing the Bitnami Redmine Package. It promises point-and-click install, and a self-contained environment with everything you need. Apart from the learning factor, are there any serious limitations this method implies? Any serious cutdowns in customizability? I will be wanting to customize the template right away, for example, and install plugins. The package looks o.k. to me but before I install it, I was curious to know whether anybody would advise against it and why. Edit: The first impression is great. From 0 to a working Redmine installation in twelve minutes! Wow.

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  • What's wrong with debugging in Eclipse on Android?

    - by Sebastian Dwornik
    I've obviously been spoiled by Visual Studio, because although I'm just learning Android and the Eclipse environment, debugging apps in Eclipse is becoming a serious detriment to further development. For example, Eclipse will compile this divide by zero just fine: public class Lesson2Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate (savedInstanceState); int i = 1 / 0; TextView tv = new TextView (this); tv.setText ("Hello, Android!"); setContentView (tv); } } And then, when it executes it under the debugger, I will get a full screen of useless debug info, non of which actually points me to the specific line containing the error. The stackTrace is null within the exception ('e') info tree, and it simply states a message stating 'ArithmeticException'. (that's nice, how about you point me in the direction of where you found it!?) I've looked all over the screen and am baffled that this IDE can't get this right. Does developing with Eclipse resort everyone back to 1991 with printf() like logging at every interval then to track down bugs? Seriously. Is there a configuration or plug-in that I'm missing to help with this? I haven't tested this case with XCode, but if the iPhone dev. IDE handles this more like Visual Studio, then no wonder the Android marketplace has so few apps. I'm excited about Android, but it seems that Eclipse is getting in the way.

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  • What does O(log n) mean exactly?

    - by Andreas Grech
    I am currently learning about Big O Notation running times and amortized times. I understand the notion of O(n) linear time, meaning that the size of the input affects the growth of the algorithm proportionally...and the same goes for, for example, quadratic time O(n2) etc..even algorithms, such as permutation generators, with O(n!) times, that grow by factorials. For example, the following function is O(n) because the algorithm grows in proportion to its input n: f(int n) { int i; for (i = 0; i < n; ++i) printf("%d", i); } Similarly, if there was a nested loop, the time would be O(n2). But what exactly is O(log n)? For example, what does it mean to say that the height of a complete binary tree is O(log n)? I do know (maybe not in great detail) what Logarithm is, in the sense that: log10 100 = 2, but I cannot understand how to identify a function with a logarithmic time.

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  • What's next for all of these Microsoft "overlapping" and "enhanced" products ?

    - by pointlesspolitics
    Recently I attended a road show, organised by MS Gold Partner company in the UK. The products discussed were: SharePoint server (2010 and 2007), Exchange server, Office Communication Server 2007, Exchange hosted services Office Live meeting, Office Communicator, System Center Configuration Manager and Operation Manager, VMware, Windows 7 etc. As Microsoft claims the enhancement in the each product against higher version, I felt that clients are not much interested in all these details. For example Office Communicator, surely they have improved a lot the product and first site all said 'WOW' great product, but nobody wish to pay money for all these extra features. Some argued, they are bogged down by all these increased number of menus. They don't need soft call feature included with mobile call. It apply for all other products as well such as MS office (next what 2 ribbons ?), windows OS and many more. Indeed there must be good features in all these products, but is it worth to spend money and time to update the older system ? Also sometimes these feature will decrease the productivity instead increase it. *So do you think what ever enhancement MS is doing in the products is only for selling purpose, not a real use ?? and I think also keep the developer busy learning the new tools and features. * I am sure some some people here will argue that some people need this sort of features. But I am not talking about NASA or MI5 guys. I am talking of usual businesses and joe public. Any ideas welcome.

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  • How do I pass a lot of parameters to views in Dango?

    - by Mark
    I'm very new to Django and I'm trying to build an application to present my data in tables and charts. Till now my learning process went very smooth, but now I'm a bit stuck. My pageview retrieves large amounts of data from a database and puts it in the context. The template then generates different html-tables. So far so good. Now I want to add different charts to the template. I manage to do this by defining <img src=".../> tags. The Matplotlib chart is generate in my chartview an returned via: response=HttpResponse(content_type='image/png') canvas.print_png(response) return response Now I have different questions: the data is retrieved twice from the database. Once in the pageview to render the tables, and again in the chartview for making the charts. What is the best way to pass the data, already in the context of the page to the chartview? I need a lot of charts, each with different datasets. I could make a chartview for each chart, but probably there is a better way. How do I pass the different dataset names to the chartview? Some charts have 20 datasets, so I don't think that passing these dataset parameters via the url (like: <imgm src="chart/dataset1/dataset2/.../dataset20/chart.png />) is the right way. Any advice?

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