Search Results

Search found 7086 results on 284 pages for 'explain'.

Page 177/284 | < Previous Page | 173 174 175 176 177 178 179 180 181 182 183 184  | Next Page >

• c++ signatures, pointers

  - by coubeatczech

  Hello, what's the difference between these signatures? T * f(T & identifier); T & f(T & identifier); T f(T & identifier); void f(T * identifier); void f(T & identifier); void f(T identifier); I met pointers in c, but the amperstand in function signature is new for me. Can Anyone explain this?

  Read the article

• Why isn't the eigenclass equivalent to self.class, when it looks so similar?

  - by The Wicked Flea

  I've missed the memo somewhere, and I hope you'll explain this to me. Why is the eigenclass of an object different from self.class? class Foo def initialize(symbol) eigenclass = class << self self end eigenclass.class_eval do attr_accessor symbol end end end My train of logic that equates the eigenclass with class.self is rather simple: class << self is a way of declaring class methods, rather than instance methods. It's a shortcut to def Foo.bar. So within the reference to the class object, returning self should be identical to self.class. This is because class << self would set self to Foo.class for definition of class methods/attributes. Am I just confused? Or, is this a sneaky trick of Ruby meta-programming?

  Read the article

• Why can I derived from a templated/generic class based on that type in C# / C++

  - by stusmith

  Title probably doesn't make a lot of sense, so I'll start with some code: class Foo : public std::vector<Foo> { }; ... Foo f; f.push_back( Foo() ); Why is this allowed by the compiler? My brain is melting at this stage, so can anyone explain whether there are any reasons you would want to do this? Unfortunately I've just seen a similar pattern in some production C# code and wondered why anyone would use this pattern.

  Read the article

• How messages flows between computers connected with Internet or LAN ?

  - by Praveen

  Hi All, I have been doing Windows programming in .Net since last two years. Now I am shifting to web programming so I just stuck in understanding the fundamentals of web programming, after googling I came to StackOverflow to learn from all of you great guys. My confusion is about how messages flow between systems in distributed enviornment ? I mean suppose I want to send a message "Hello" to a system connected to LAN or Internet, then what will be the steps taken to send the message. Second thing is suppose my system is "A" and I wana send message to system "B" which is connected via a wire, so how the message flows on wire and how system "B" reads it from the wire ? Please someone explain me in a layman terms. Thank you all in advance.

  Read the article

• Displaying same icon in 2 different sizes on c#

  - by ET

  My goal is to display the same icon twice, but each time in different size. I tried the following: FileStream fs = new FileStream("name_of_the_icon_file.ico", FileMode.Open); Icon ico = new Icon(fs, 32, 32); //create an in-memory instance of the icon, size 32x32 Icon ico2 = new Icon(fs, 16, 16); //create an in-memory instance of the icon, size 16x16 ... Graphics.DrawIcon(ico, /*some point*/); Graphics.DrawIcon(ico2, /*some other point*/); The last line throws an ArgumentException: Value does not fall within the expected range. Can some one explain me whats wrong and whats the way to do this right?

  Read the article

• strenge exception phenomenon in win7

  - by Level 2

  Hello all, I spot some interesting artcles about exception handle in codeproject http://www.codeproject.com/KB/cpp/seexception.aspx after reading, I decided to do some experiment. The first time I try to excute the following code char *p; p[0] = 0; The program died without question. But After serveral time I execute the same problem binary code. It magically did fine. even the following code is doing well. any clue or explain? char *p p[1000] = 'd'; cout<<p[1000]<<endl; my os is windows 7 64bit and compiler is vs2008 rc1.

  Read the article

• Why does Perl allow mutual "use" relationships between modules?

  - by Haiyuan Zhang

  Let's say there are two modules that mutually use each other: package a; use b; sub p {} 1; package b; use a; 1; I think that it is systematically wrong to write code like the above, because the two modules will endlessly copy each other's code to themselves, but I can successfully run the following code, which makes me very surprised. Could any of you explain all of this to me? #! /usr/bin/perl use a; a->p();

  Read the article

• Launch ms word template as new document from IE...

  - by Simon

  I have a requirement to launch .dot files (ms word templates) as new documents from the browser... Let me explain... if you click on a .dot file in Windows Explorer it opens a new document and runs any macros... you can right click and edit the template... I want to link to the files, so I use <a href="file://myserver/templates/letter.dot">Letter</a>... However this then prompts for the "Download File" dialogue box... and then if I click "Open" it opens the template in edit mode... not the required new document mode... This may be a technical impossibility but can I achieve the desired result in ActiveX or something??

  Read the article

• How to declare and use the name of a function from a json object?

  - by Sebastian

  Hello, I have a json object collection of geo locations that I build in the server. Each of those objects has two properties: "marker" and "onClick". Marker is for storing a Google Maps marker object and the onClick stores the name of the function to be called when that marker is clicked on the map. When I'm pushing the location objects into an array using javascript in the client side, I create the markers and assign them to each location object within the array. My problem is that when I bind the marker with the onClick property, the function won't be found in the DOM and get an error. Is there a way to declare a property in a json object for using it on an event binding? Hope I could explain it clearly, if not, please let me know. Thanks!

  Read the article

• Intellij UML diagram does not show one to many relationships

  - by Calm Storm

  I am trying to follow http://www.jetbrains.com/idea/features/uml_class_diagram.html I have a few classes so when I do Ctrl + Alt + U I only see all classes and just Extends relationships. Please note that I have set the "Diagrams" options in my settings to show one to many etc. I do not see One to One, One to Many relationships at all ? I have used JPA OneToOne Annotations and they dont turn up at all? Pressing Ctrl Shift F12 does not do anything? Can someone please explain?

  Read the article

• How to save to two tables using one SQLAlchemy model

  - by Oatman

  I have an SQLAlchemy ORM class, linked to MySQL, which works great at saving the data I need down to the underlying table. However, I would like to also save the identical data to a second archive table. Here's some psudocode to try and explain what I mean my_data = Data() #An ORM Class my_data.name = "foo" #This saves just to the 'data' table session.add(my_data) #This will save it to the identical 'backup_data' table my_data_archive = my_data my_data_archive.__tablename__ = 'backup_data' session.add(my_data_archive) #And commits them both session.commit() Just a heads up, I am not interested in mapping a class to a JOIN, as in: http://www.sqlalchemy.org/docs/05/mappers.html#mapping-a-class-against-multiple-tables

  Read the article

• Zend DB inserting relational data

  - by Wimbjorno

  I'm using the Zend Framework database relationships for a couple of weeks now. My first impression is pretty good, but I do have a question related to inserting related data into multiple tables. For a little test application I've related two tables with each other by using a fuse table. +---------------+ +---------------+ +---------------+ | Pages | | Fuse | | Prints | +---------------+ +---------------+ +---------------+ | pageid | | fuseid | | printid | | page_active | | fuse_page | | print_title | | page_author | | fuse_print | | print_content | | page_created | | fuse_locale | | ... | | ... | | ... | +---------------+ +---------------+ +---------------+ Above is an example of my DB architecture Now, my problem is how to insert related data to two separate tables and insert the two newly created ID's into the fuse table at the same time. If someone could could maybe explain or give me a topic related tutorial. I would appreciate it!

  Read the article

• Could someone tell me if my C++ indent style is named? (example given)

  - by Maulrus

  I'm learning C++. For me, my programming style is just what looks the best; it doesn't seem to follow the rules of any one particular style. Here's an example void f(int x){ //no space between close-paren and bracket if (!x){ cout << "x is non-zero\n"; } //closing bracket indented to the same level as the original statement } It's only slightly different for something like a class or a namespace: class myClass {}; //space between class name and bracket, otherwise the same as functions K&R style does uses that kind of bracketing for statements, but my style uses it for everything. I'd like to know if there's a name for it so I can say simply what my indent style is without having to explain using examples like these.

  Read the article

• Using pthread condition variable with rwlock

  - by Doomsday

  Hello, I'm looking for a way to use pthread rwlock structure with conditions routines in C++. I have two questions: First: How is it possible and if we can't, why ? Second: Why current POSIX pthread have not implemented this behaviour ? To understand my purpose, I explain what will be my use: I've a producer-consumer model dealing with one shared array. The consumer will cond_wait when the array is empty, but rdlock when reading some elems. The producer will wrlock when adding(+signal) or removing elems from the array. The benefit of using rdlock instead of mutex_lock is to improve performance: when using mutex_lock, several readers would block, whereas using rdlock several readers would not block.

  Read the article

• Why can't we use strong ref cursor with dynamic SQL Statement?

  - by Vineet

  Hi ALL, I am trying to use a strong ref cur with dynamic sql statment but it is giving out an error,but when i use weak cursor it works,Please explain what is the reason and please forward me any link of oracle server architect containing matter about how compilation and parsing is done in Oracle server. THIS is the error along with code. ERROR at line 6: ORA-06550: line 6, column 7: PLS-00455: cursor 'EMP_REF_CUR' cannot be used in dynamic SQL OPEN statement ORA-06550: line 6, column 2: PL/SQL: Statement ignored declare type ref_cur_type IS REF CURSOR RETURN employees%ROWTYPE; --Creating a strong REF cursor,employees is a table emp_ref_cur ref_cur_type; emp_rec employees%ROWTYPE; BEGIN OPEN emp_ref_cur FOR 'SELECT * FROM employees'; LOOP FETCH emp_ref_cur INTO emp_rec; EXIT WHEN emp_ref_cur%NOTFOUND; END lOOP; END;

  Read the article

• Tag <code>: how to "correct" publish it ?

  - by stighy

  Hi, i'm not sure to explain what i'm looking for. What's the name of the "source code parser" for publish code, in HTML ? For example, when i write some source code here in stack overflow, system auto-detect the sintax and write "correct" source code in html. I've noticed that exists the HTML <"code" tag, but it simply write source code in "courier" font. So i'm asking you if exists some "external" component that, given a text, parse it out correctly in a HTML page. Thank you!

  Read the article

• Htaccess/robots.txt to allow search bots to explore main domain but not directory on other domain

  - by gX

  Ok, I understand the Title didn't make any sense so here I've tried to explain it in detail. I'm using a hosting that gives me space for my domain and lets me "add on" other domains on it. So lets say I have a domain A, and I add on a domain B. Basically my hosting gives me a public_html where I can put stuff that shows when someone visits website A. But, when I add the domain B, it lets me put the content of B, INSIDE of that public_html so that website B.com can also be visited by going to A.com/siteB... Thats all good, except that Google has started indexing B.com as well as A.com/siteB, I'm ok with it indexing B.com, but I somehow want to prevent it from indexing A.com/siteB so that when people search for B, it doesn't end up showing A.com/siteB. Any ideas? Let me know if the question is still unclear.

  Read the article

• Why PHP (script) serves more requests than CGI (compiled)?

  - by Lucas Batistussi

  I developed the following CGI script and run on Apache 2 (http://localhost/test.chtml). I did same script in PHP (http://localhost/verifica.php). Later I performed Apache benchmark using Apache Benchmark tool. The results are showed in images. include #include <stdlib.h> int main(void) { printf("%s%c%c\n", "Content-Type:text/html;charset=iso-8859-1",13,10); printf("<TITLE>Multiplication results</TITLE>\n"); printf("<H3>Multiplication results</H3>\n"); return 0; } Someone can explain me why PHP serves more requests than CGI script?

  Read the article

• date() returning wrong day although the timestamp is correct!

  - by Spiros

  I have a bizzare problem with php date function. code: $numDays = 8; $date = strtotime('2010-11-06'); for ($i=1; $i<=$numDays; $i++) { $thisDay = date("D, d M Y", $date); print ($thisDay.'<br>'); $date+=86400; // add one day to timestamp } result on my server (local host, windows): Sat, 06 Nov 2010 Sun, 07 Nov 2010 Mon, 08 Nov 2010 Tue, 09 Nov 2010 Wed, 10 Nov 2010 Thu, 11 Nov 2010 Fri, 12 Nov 2010 Sat, 13 Nov 2010 Result on my web server (linux) Sat, 06 Nov 2010 *Sun, 07 Nov 2010 Sun, 07 Nov 2010* Mon, 08 Nov 2010 Tue, 09 Nov 2010 Wed, 10 Nov 2010 Thu, 11 Nov 2010 Fri, 12 Nov 2010 Notice how Sun, 07 Nov 2010 appears twice on the remote server?? Why is this happening? can anyone explain this Behavior?

  Read the article

• One of my IFrames not displaying.

  - by user323186

  Im writing a page consisting of a navigation bar which when ckicked will open other pages in an IFrame below. Its working in general, but one of my Iframes doesnt display. I cannot for the life of me explain why. If you can see why please tell me. Its the google button that doesnt work. Please find my website in the zip archive: http://www.datafilehost.com/download-a9f59084.html The page to view to test is: /Navbar/homeDiv2.html Any suggestions appreciated. Thanks

  Read the article

• Proper use of use of "cor" function in R

  - by order

  I am interested to know what a proper x (vector matrix or data frame) input looks like. I am currently using the function in two different sorts of matrices. However, I am not sure how R would interpret my data the way I intend. I will explain the types of matrix by example. Type 1 Gene1 Gene2 Gene3 sample1 sample2 Type 2 Sample1 Sample2 Sample3 gene 1 gene 2 gene 3 Are either of these formats valid x parameters? I input both of types of matrices and get some results, but without knowing whether or not this a proper use the function, these are just random numbers. Thank you for your time. I apologize that this isn't more interesting.

  Read the article

• Simple OOP-related question.

  - by M4design

  This question came to my mind quite a few times. Let my explain my question through an example. Say I've got two classes: 1- Grid. 2- Cell. Now the location of the cell 'should' be stored in the grid class, not in the cell class itself. Say that the cell wanted to get its location through a method in the grid. How can it do that? Keep in mind that the cell was created/initialised by the Grid class. What good OO approach to solve this problem? Thank you

  Read the article

• Python built-in id() not consistent:

  - by Dannellyz

  Hoping someone can explain the following discrepancy: >>> s1 = "Cyber security" >>> s2 = "Cyber security" >>> id(s1) == id(s1) True >>> id(s1) == id(s2) False >>> s1 = "cyber" >>> s2 = "cyber" >>> id(s1) == id(s2) True >>> s2 = "cyber " >>> s2 = "cyber " >>> id(s1) == id(s2) False Why does the space make the id() False, yet different variables with no spaces are True?

  Read the article

• perf events documentation

  - by Thanatos

  I've searched for an exhaustive explanation of the meaning of each event monitored by the perf stat command; I've found a tutorial which explains quite well how to use different the features of the perf tool. However, it doesn't explain the meaning of several events that can be observed (and there are a lot!!). Someone know where is a quite simple and complete documentation about the events listed by the perf list command? In particular, I'm interested in finding out the percentage of cpu used by some application I wrote. Can i measure it directly through cpu-clock or task-clock? What's the meaning of these two events? Thanks in advance

  Read the article

• Compilation Error related

  - by aparna

  Given: 11. public static void test(String str) { 12. int check = 4; 13. if (check = str.length()) { 14. System.out.print(str.charAt(check -= 1) +", "); 15. } else { 16. System.out.print(str.charAt(0) + ", "); 17. } 18. } and the invocation: 21. test("four"); 22. test("tee"); 23. test("to"); What is the result? A. r, t, t, B. r, e, o, C. Compilation fails. D. An exception is thrown at runtime. Answer: C Can you explain why the compilation fails please?

  Read the article

< Previous Page | 173 174 175 176 177 178 179 180 181 182 183 184  | Next Page >