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• Connect Rails model to non-rails database

  - by the_snitch

  I'm creating a new web application (Rails 3 beta), of which pieces of it will access data from a legacy mysql database that a current php application is using. I do not wish to modify the legacy db schema, I just want to be able to read/write to it, as well as the rails application having it's own database using activerecord for the newer stuff. I'm using mysql for the rails app, so I have the adapter installed. How is the best way to do this? For example, I want contacts to come from the old database. Should I create a contacts controller, and manually call sql to get the variables for the views? Or should I create a Contact model, and define attributes that match the fields in the database, and am I able to use it like Contact.mail_address to have it call "SELECT mailaddr FROM contacts WHERE id=Contact.id". Sorry, I've never done much in Rails outside of the standard stuff that is documented well. I'm not sure of what the best approach would be. Ideally, I want the contacts to be presented to my rails application as native as possible, so that I can expose them RESTfully for API access. Any suggestions and code examples would be much appreciated

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• Create static instances of a class inside said class in Python

  - by Samir Talwar

  Apologies if I've got the terminology wrong here—I can't think what this particular idiom would be called. I've been trying to create a Python 3 class that statically declares instances of itself inside itself—sort of like an enum would work. Here's a simplified version of the code I wrote: class Test: A = Test("A") B = Test("B") def __init__(self, value): self.value = value def __str__(self): return "Test: " + self.value print(str(Test.A)) print(str(Test.B)) Writing this, I got an exception on line 2 (A = Test("A")). I assume line 3 would also error if it had made it that far. Using __class__ instead of Test gives the same error. File "<stdin>", line 1, in <module> File "<stdin>", line 2, in Test NameError: name 'Test' is not defined Is there any way to refer to the current class in a static context in Python? I could declare these particular variables outside the class or in a separate class, but for clarity's sake, I'd rather not if I can help it. To better demonstrate what I'm trying to do, here's the same example in Java: public class Test { private static final Test A = new Test("A"); private static final Test B = new Test("B"); private final String value; public Test(String value) { this.value = value; } public String toString() { return "Test: " + value; } public static void main(String[] args) { System.out.println(A); System.out.println(B); } } This works as you would expect: it prints: Test: A Test: B How can I do the same thing in Python?

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• Saving temporary file name after uploading file with uplodify

  - by mIRU

  I have this script if (!empty($_FILES)) { $tempFile = $_FILES['Filedata']['tmp_name']; $targetPath = dirname(__FILE__).$_POST['folder'] . '/'; $pathinfoFile = pathinfo($_FILES['Filedata']['name']); $targetFile = str_replace('//','/',$targetPath) .uniqid().'.'.$pathinfoFile['extension']; move_uploaded_file($tempFile,$targetFile); } this script is from uplodify , modified for saving the file with unique name , i need after user will upload the file , this unique name and original name , to save temporary , when user will submit the form , this temporary variables i will insert in database , the problem is that in firebug console , i can not see all the actions of this script , and i can not understand the way how to fix it, I tried to save in $_SESSION but i have problems , is not saving , i found why is not working with $_SESSION , http://uploadify.com/forum/viewtopic.php?f=5&t=43 , i tried the solution from forum but without result , exist a more easy way to solve this problem ? , or what is better way to do it ? . Sorry for so silly question , i ran out of ideas . Thanks a lot for helping me , and sorry again for my English

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• iOS - Passing variable to view controller

  - by gj15987

  I have a view with a view controller and when I show this view on screen, I want to be able to pass variables to it from the calling class, so that I can set the values of labels etc. First, I just tried creating a property for one of the labels, and calling that from the calling class. For example: SetTeamsViewController *vc = [[SetTeamsViewController alloc] init]; vc.myLabel.text = self.teamCount; [self presentModalViewController:vc animated:YES]; [vc release]; However, this didn't work. So I tried creating a convenience initializer. SetTeamsViewController *vc = [[SetTeamsViewController alloc] initWithTeamCount:self.teamCount]; And then in the SetTeamsViewController I had - (id)initWithTeamCount:(int)teamCount { self = [super initWithNibName:nil bundle:nil]; if (self) { // Custom initialization self.teamCountLabel.text = [NSString stringWithFormat:@"%d",teamCount]; } return self; } However, this didn't work either. It's just loading whatever value I've given the label in the nib file. I've littered the code with NSLog()s and it is passing the correct variable values around, it's just not setting the label. Any help would be greatly appreciated. EDIT: I've just tried setting an instance variable in my designated initializer, and then setting the label in viewDidLoad and that works! Is this the best way to do this? Also, when dismissing this modal view controller, I update the text of a button in the view of the calling ViewController too. However, if I press this button again (to show the modal view again) whilst the other view is animating on screen, the button temporarily has it's original value again (from the nib). Does anyone know why this is?

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• How to check whether user is login in web application?

  - by Morgan Cheng

  I want to learn the whole details of web application authentication. So, I decided to write a CodeIgniter authentication library from scratch. Now, I have to make design decision about how to determine whether one user is login. Basically, after user input username & password pair. A cookie is set for this session, following navigations in the web application will not require username & password. The server side will check whether the session cookie is valid to determine whether current user is login. The question is: how to determine whether cookie is valid cookie issued from server side? I can image the most simple way is to have the cookie value stored in session status as well. For each HTTP request, compare the value from cookie and the value from server session. (Since CodeIgniter session library store session variables in cookies, it is not applicable without some tweak.) This method requires storage in server side. For huge web application that is deployed in multiple datacenters. It is possible that user input username & password when browsing in one datacenter, while he/she access the web application in another datacenter later. The expected behavior is that user just input username & password once. As a result, all datacenters should be able to access the session status. That is possible not applicable even the session status is stored in external storage such as database. I tried Google. I login Google with Asian proxy which is supposed to direct me to datacenters in Asian. Then I switch to North American proxy which should direct me to datacenters in North America. It recognize my login without asking username and password again. So, is there any way to determine whether user is login without server side session status?

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• Converting contents of a byte array to wchar_t*

  - by Christopher MacKinnon

  I seem to be having an issue converting a byte array (containing the text from a word document) to a LPTSTR (wchar_t *) object. Every time the code executes, I am getting a bunch of unwanted Unicode characters returned. I figure it is because I am not making the proper calls somewhere, or not using the variables properly, but not quite sure how to approach this. Hopefully someone here can guide me in the right direction. The first thing that happens in we call into C# code to open up Microsoft Word and convert the text in the document into a byte array. byte document __gc[]; document = word->ConvertToArray(filename); The contents of document are as follows: {84, 101, 115, 116, 32, 68, 111, 99, 117, 109, 101, 110, 116, 13, 10} Which ends up being the following string: "Test Document". Our next step is to allocate the memory to store the byte array into a LPTSTR variable, byte __pin * value; value = &document[0]; LPTSTR image; image = (LPTSTR)malloc( document->Length + 1 ); Once we execute the line where we start allocating the memory, our image variable gets filled with a bunch of unwanted Unicode characters: ????????????????? And then we do a memcpy to transfer over all of the data memcpy(image,value,document->Length); Which just causes more unwanted Unicode characters to appear: ????????????????? I figure the issue that we are having is either related to how we are storing the values in the byte array, or possibly when we are copying the data from the byte array to the LPTSTR variable. Any help with explaining what I'm doing wrong, or anything to point me in the right direction will be greatly appreciated.

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• Obtaining FontMetrics before getting a Graphics instance

  - by Tom Castle

  Typically, I'd obtain a graphics instance something like this: BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB); Graphics2D g = img.createGraphics(); However, in the current project I'm working on, the width and height variables above are dependent upon the size of a number of text fragments that will later be drawn onto the graphics instance. But, to obtain the dimensions of the font being used I would usually use the FontMetrics that I get from the graphics object. FontMetrics metrics = g.getFontMetrics(); So, I have a nasty little dependency cycle. I cannot create the graphics object until I know the size of the text, and I cannot know the size of the text until I have a graphics object. One solution is just to create another BufferedImage/Graphics pair first in order to get the FontMetrics instance I need, but this seems unnecessary. So, is there a nicer way? Or is it the case that the width, height etc. properties for a Font are somehow dependent upon what (graphics, component...) the text is to be drawn on?

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• Filtering a PHP array containing dates into a yearly summary

  - by privateace

  I'm looking at a way to create a summary of transactions within a certain month based on the contents of a PHP array. Intended outcome (excusing layout): ------------------------------------------- | December 2009 | 12 | | January 2010 | 02 | | February 2010 | 47 | | March 2010 | 108 | | April 2010 | 499 | ------------------------------------------- Based on my array: Array ( [0] => Array ( [name] => 2009-10-23 [values] => Array ( [0] => INzY2MTI4ZWM4OGRm ) ) [1] => Array ( [name] => 2009-10-26 [values] => Array ( [0] => IYmIzOWNmMmU3OWQz ) ) [2] => Array ( [name] => 2009-11-23 [values] => Array ( [0] => INTg4YzgxYWU1ODkx [1] => IMjhkNDZkY2FjNDhl ) ) [3] => Array ( [name] => 2009-11-24 [values] => Array ( [0] => INTg4YzgxYWU1ODkx [1] => INTg4YzgxYWU1ODkx ) ) [4] => Array ( [name] => 2009-12-01 [values] => Array ( [0] => IMWFiODk5ZjU1OTFk ) ) I've had absolutely no luck no matter what I've tried. Especially with adding months that do not contain any variables.

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• How to store and remove dynamically and automatic variable of generic data type in custum list data

  - by Vineel Kumar Reddy

  Hi I have created a List data structure implementation for generic data type with each node declared as following. struct Node { void *data; .... .... } So each node in my list will have pointer to the actual data(generic could be anything) item that should be stored in the list. I have following signature for adding a node to the list AddNode(struct List *list, void* eledata); the problem is when i want to remove a node i want to free even the data block pointed by *data pointer inside the node structure that is going to be freed. at first freeing of datablock seems to be straight forward free(data) // forget about the syntax..... But if data is pointing to a block created by malloc then the above call is fine....and we can free that block using free function int *x = (int*) malloc(sizeof(int)); *x = 10; AddNode(list,(void*)x); // x can be freed as it was created using malloc what if a node is created as following int x = 10; AddNode(list,(void*)&x); // x cannot be freed as it was not created using malloc Here we cannot call free on variable x!!!! How do i know or implement the functionality for both dynamically allocated variables and static ones....that are passed to my list.... Thanks in advance...

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• R: Are there any alternatives to loops for subsetting from an optimization standpoint?

  - by Adam

  A recurring analysis paradigm I encounter in my research is the need to subset based on all different group id values, performing statistical analysis on each group in turn, and putting the results in an output matrix for further processing/summarizing. How I typically do this in R is something like the following: data.mat <- read.csv("...") groupids <- unique(data.mat$ID) #Assume there are then 100 unique groups results <- matrix(rep("NA",300),ncol=3,nrow=100) for(i in 1:100) { tempmat <- subset(data.mat,ID==groupids[i]) #Run various stats on tempmat (correlations, regressions, etc), checking to #make sure this specific group doesn't have NAs in the variables I'm using #and assign results to x, y, and z, for example. results[i,1] <- x results[i,2] <- y results[i,3] <- z } This ends up working for me, but depending on the size of the data and the number of groups I'm working with, this can take up to three days. Besides branching out into parallel processing, is there any "trick" for making something like this run faster? For instance, converting the loops into something else (something like an apply with a function containing the stats I want to run inside the loop), or eliminating the need to actually assign the subset of data to a variable?

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• SSRS code variable resetting on new page

  - by edmicman

  In SSRS 2008 I am trying to maintain a SUM of SUMs on a group using custom Code. The reason is that I have a table of data, grouped and returning SUMs of the data. I have a filter on the group to remove lines where group sums are zero. Everything works except I'm running into problems with the group totals - it should be summing the visible group totals but is instead summing the entire dataset. There's tons of articles about how to work around this, usually using custom code. I've made custom functions and variables to maintain a counter: Public Dim GroupMedTotal as Integer Public Dim GrandMedTotal as Integer Public Function CalcMedTotal(ThisValue as Integer) as Integer GroupMedTotal = GroupMedTotal + ThisValue GrandMedTotal = GrandMedTotal + ThisValue Return ThisValue End Function Public Function ReturnMedSubtotal() as Integer Dim ThisValue as Integer = GroupMedTotal GroupMedTotal = 0 Return ThisValue End Function Basically CalcMedTotal is fed a SUM of a group, and maintains a running total of that sum. Then in the group total line I output ReturnMedSubtotal which is supposed to give me the accumulated total and reset it for the next group. This actually works great, EXCEPT - it is resetting the GroupMedTotal value on each page break. I don't have page breaks explicitly set, it's just the natural break in the SSRS viewer. And if I export the results to Excel everything works and looks correctly. If I output Code.GroupMedTotal on each group row, I see it count correctly, and then if a group spans multiple pages on the next page GroupMedTotal is reset and begins counting from zero again. Any help in what's going on or how to work around this? Thanks!

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• High precision event timer

  - by rahul jv

  #include "target.h" #include "xcp.h" #include "LocatedVars.h" #include "osek.h" /** * This task is activated every 10ms. */ long OSTICKDURATION; TASK( Task10ms ) { void XCP_FN_TYPE Xcp_CmdProcessor( void ); uint32 startTime = GetQueryPerformanceCounter(); /* Trigger DAQ for the 10ms XCP raster. */ if( XCPEVENT_DAQ_OVERLOAD & Xcp_DoDaqForEvent_10msRstr() ) { ++numDaqOverload10ms; } /* Update those variables which are modified every 10ms. */ counter16 += slope16; /* Trigger STIM for the 10ms XCP raster. */ if( enableBypass10ms ) { if( XCPEVENT_MISSING_DTO & Xcp_DoStimForEvent_10msRstr() ) { ++numMissingDto10ms; } } duration10ms = (uint32)( ( GetQueryPerformanceCounter() - startTime ) / STOPWATCH_TICKS_PER_US ); } What would be the easiest (and/or best) way to synchronise to some accurate clock to call a function at a specific time interval, with little jitter during normal circumstances, from C++? I am working on WINDOWS operating system now. The above code is for RTAS OSEK but I want to call a function at a specific time interval for windows operating system. Could anyone assist me in c++ language ??

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• Trouble with pointers and references in C++

  - by KingNestor

  I have a PolygonList and a Polygon type, which are std::lists of Points or lists of lists of points. class Point { public: int x, y; Point(int x1, int y1) { x = x1; y = y1; } }; typedef std::list<Point> Polygon; typedef std::list<Polygon> PolygonList; // List of all our polygons PolygonList polygonList; However, I'm confused on reference variables and pointers. For example, I would like to be able to reference the first Polygon in my polygonList, and push a new Point to it. So I attempted to set the front of the polygonList to a Polygon called currentPolygon like so: Polygon currentPolygon = polygonList.front(); currentPolygon.push_front(somePoint); and now, I can add points to currentPolygon, but these changes end up not being reflected in that same polygon in the polygonList. Is currentPolygon simply a copy of the Polygon in the front of polygonList? When I later iterate over polygonList all the points I've added to currentPolygon aren't shown. It works if I do this: polygonList.front().push_front(somePoint); Why aren't these the same and how can I create a reference to the physical front polygon rather than a copy of it?

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• Run arbitrary subprocesses on Windows and still terminate cleanly?

  - by Weeble

  I have an application A that I would like to be able to invoke arbitrary other processes as specified by a user in a configuration file. Batch script B is one such process a user would like to be invoked by A. B sets up some environment variables, shows some messages and invokes a compiler C to do some work. Does Windows provide a standard way for arbitrary processes to be terminated cleanly? Suppose A is run in a console and receives a CTRL+C. Can it pass this on to B and C? Suppose A runs in a window and the user tries to close the window, can it cancel B and C? TerminateProcess is an option, but not a very good one. If A uses TerminateProcess on B, C keeps running. This could cause nasty problems if C is long-running, since we might start another instance of C to operate on the same files while the first instance of C is still secretly at work. In addition, TerminateProcess doesn't result in a clean exit. GenerateConsoleCtrlEvent sounds nice, and might work when everything's running in a console, but the documentation says that you can only send CTRL+C to your own console, and so wouldn't help if A were running in a window. Is there any equivalent to SIGINT on Windows? I would love to find an article like this one: http://www.cons.org/cracauer/sigint.html for Windows.

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• reshaping a data frame into long format in R

  - by user1773115

  I'm struggling with a reshape in R. I have 2 types of error (err and rel_err) that have been calculated for 3 different models. This gives me a total of 6 error variables (i.e. err_1, err_2, err_3, rel_err_1, rel_err_2, and rel_err_3). For each of these types of error I have 3 different types of predivtive validity tests (ie random holdouts, backcast, forecast). I would like to make my data set long so I keep the 4 types of test long while also making the two error measurements long. So in the end I will have one variable called err and one called rel_err as well as an id variable for what model the error corresponds to (1,2,or 3) Here is my data right now: iter err_1 rel_err_1 err_2 rel_err_2 err_3 rel_err_3 test_type 1 -0.09385732 -0.2235443 -0.1216982 -0.2898543 -0.1058366 -0.2520759 random 1 0.16141630 0.8575728 0.1418732 0.7537442 0.1584816 0.8419816 back 1 0.16376930 0.8700738 0.1431505 0.7605302 0.1596502 0.8481901 front 1 0.14345986 0.6765194 0.1213689 0.5723444 0.1374676 0.6482615 random 1 0.15890059 0.7435382 0.1589823 0.7439204 0.1608709 0.7527580 back 1 0.14412360 0.6743928 0.1442039 0.6747684 0.1463520 0.6848202 front and here is what I would like it to look like: iter model err rel_err test_type 1 1 -0.09385732 (#'s) random 1 2 -0.1216982 (#'s) random 1 3 -0.1216982 (#'s) random and on... I've tried playing around with the syntax but can't quite figure out what to put for the time.varying argument Thanks very much for any help you can offer.

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• Can someone explain the declaration of these java generic methods?

  - by Tony Giaccone

  I'm reading "Generics in the Java Programming Language" by Gilad Bracha and I'm confused about a style of declaration. The following code is found on page 8: interface Collection<E> { public boolean containsAll(Collection<?> c); public boolean addAll(Collection<? extends E> c); } interface Collection<E> { public <T> boolean containsAll(Collection<T> c); public <T extends E> boolean addAll(Collection<T> c); // hey, type variables can have bounds too! } My point of confusion comes from the second declaration. It's not clear to me what the purpose the <T> declaration serves in the following line: public <T> boolean containsAll(Collection<T> c); The method already has a type (boolean) associated with it. Why would you use the <T> and what does it tell the complier? I think my question needs to be a bit more specific. Why would you write: public <T> boolean containsAll(Collection<T> c); vs public boolean containsAll(Collection<T> c); It's not clear to me, what the purpose of <T> is, in the first declaration of containsAll.

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• Is there a definitive reference document for Ruby syntax?

  - by JSW

  I'm searching for a definitive document on Ruby syntax. I know about the definitive documents for the core API and standard library, but what about the syntax itself? For instance, such a document should cover: reserved words, string literals syntax, naming rules for variables/classes/modules, all the conditional statements and their permutations, and so forth. I know there are many books and tutorials, yes, but every one of them is essentially a tutorial, each one having a range of different depth and focus. They will all, by necessity of brevity and narrative flow, omit certain details of the language that the author deems insignificant. For instance, did you know that you can use a case statement without an initial case value, and it will then execute the first true when clause? Any given Ruby book or tutorial may or may not cover that particular lesser-known functionality of the case syntax. It's not discussed in the section in "Programming Ruby" about case statements. But that is just one small example. So far the best documentation I've found is the rubyspec project, which appears to be an attempt to write a complete test suite for the language. That's not bad, but it's a bit hard to use from a practical standpoint as a developer working on my own projects. Am I just missing something or is there really no definitive readable document defining the whole of Ruby syntax?

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• Can C++ do something like an ML case expression?

  - by Nathan Andrew Mullenax

  So, I've run into this sort of thing a few times in C++ where I'd really like to write something like case (a,b,c,d) of (true, true, _, _ ) => expr | (false, true, _, false) => expr | ... But in C++, I invariably end up with something like this: bool c11 = color1.count(e.first)>0; bool c21 = color2.count(e.first)>0; bool c12 = color1.count(e.second)>0; bool c22 = color2.count(e.second)>0; // no vertex in this edge is colored // requeue if( !(c11||c21||c12||c22) ) { edges.push(e); } // endpoints already same color // failure condition else if( (c11&&c12)||(c21&&c22) ) { results.push_back("NOT BICOLORABLE."); return true; } // nothing to do: nodes are already // colored and different from one another else if( (c11&&c22)||(c21&&c12) ) { } // first is c1, second is not set else if( c11 && !(c12||c22) ) { color2.insert( e.second ); } // first is c2, second is not set else if( c21 && !(c12||c22) ) { color1.insert( e.second ); } // first is not set, second is c1 else if( !(c11||c21) && c12 ) { color2.insert( e.first ); } // first is not set, second is c2 else if( !(c11||c21) && c22 ) { color1.insert( e.first ); } else { std::cout << "Something went wrong.\n"; } I'm wondering if there's any way to clean all of those if's and else's up, as it seems especially error prone. It would be even better if it were possible to get the compiler complain like SML does when a case expression (or statement in C++) isn't exhaustive. I realize this question is a bit vague. Maybe, in sum, how would one represent an exhaustive truth table with an arbitrary number of variables in C++ succinctly? Thanks in advance.

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• Any problems with this C++ const reference accessor interface idiom?

  - by mskfisher

  I was converting a struct to a class so I could enforce a setter interface for my variables. I did not want to change all of the instances where the variable was read, though. So I converted this: struct foo_t { int x; float y; }; to this: class foo_t { int _x; float _y; public: foot_t() : x(_x), y(_y) { set(0, 0.0); } const int &x; const float &y; set(int x, float y) { _x = x; _y = y; } }; I'm interested in this because it seems to model C#'s idea of public read-only properties. Compiles fine, and I haven't seen any problems yet. Besides the boilerplate of associating the const references in the constructor, what are the downsides to this method? Any strange aliasing issues? Why haven't I seen this idiom before?

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• C++ Constructor initialization list strangeness

  - by Andy

  I have always been a good boy when writing my classes, prefixing all member variables with m_: class Test { int m_int1; int m_int2; public: Test(int int1, int int2) : m_int1(int int1), m_int2(int int2) {} }; void main() { Test t(10, 20); // Just an example } However, recently I forgot to do that and ended up writing: class Test { int int1; int int2; public: // Very questionable, but of course I meant to assign ::int1 to this->int1! Test(int int1, int int2) : int1(int1), int2(int2) {} }; Believe it or not, the code compiled with no errors/warnings and the assignments took place correctly! It was only when doing the final check before checking in my code when I realised what I had done. My question is: why did my code compile? Is something like that allowed in the C++ standard, or is it simply a case of the compiler being clever? In case you were wondering, I was using Visual Studio 2008 Thank you.

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• Wrapper class that creates objects at runtime and stores data in an array.

  - by scriptingalias

  I tried making a wrapper class that encapsulates an object, a string (for naming and differentiating the object instance), and an array to store data. The problem I'm having now is accessing this class using methods that determine the "name" of the object and also reading the array containing some random variables. import java.util.Arrays; import java.util.Random; public class WrapperClass { String varName; Object varData; int[] array = new int[10]; public WrapperClass(String name, Object data, int[] ARRAY) { varName = name; varData = data; array = ARRAY; } public static void getvalues() { } public static void main(String[] args) { int[] array = new int[10]; Random random = new Random(3134234); for(int i = 0; i < 10; i++) { for (int c = 0; c < 10; c++) { array[c] = random.nextInt();//randomly creates data } WrapperClass w = new WrapperClass("c" + i, new Object(),array); } } }

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• Extremely CPU Intensive Alarm Clock

  - by SoulBeaver

  For some reason my program, a console alarm clock I made for laughs and practice, is extremely CPU intensive. It consumes about 2mB RAM, which is already quite a bit for such a small program, but it devastates my CPU with over 50% resources at times. Most of the time my program is doing nothing except counting down the seconds, so I guess this part of my program is the one that's causing so much strain on my CPU, though I don't know why. If it is so, could you please recommend a way of making it less, or perhaps a library to use instead if the problem can't be easily solved? /* The wait function waits exactly one second before returning to the * * called function. */ void wait( const int &seconds ) { clock_t endwait; // Type needed to compare with clock() endwait = clock() + ( seconds * CLOCKS_PER_SEC ); while( clock() < endwait ) {} // Nothing need be done here. } In case anybody browses CPlusPlus.com, this is a genuine copy/paste of the clock() function they have written as an example for clock(). Much why the comment //Nothing need be done here is so lackluster. I'm not entirely sure what exactly clock() does yet. The rest of the program calls two other functions that only activate every sixty seconds, otherwise returning to the caller and counting down another second, so I don't think that's too CPU intensive- though I wouldn't know, this is my first attempt at optimizing code. The first function is a console clear using system("cls") which, I know, is really, really slow and not a good idea. I will be changing that post-haste, but, since it only activates every 60 seconds and there is a noticeable lag-spike, I know this isn't the problem most of the time. The second function re-writes the content of the screen with the updated remaining time also only every sixty seconds. I will edit in the function that calls wait, clearScreen and display if it's clear that this function is not the problem. I already tried to reference most variables so they are not copied, as well as avoid endl as I heard that it's a little slow compared to \n.

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• Form validation

  - by kielie

  Hi guys, I need to create a form that has many of the same fields, that have to be inserted into a database, but the problem I have is that if a user only fills in one or two of the rows, the form will still submit the blank data of the empty fields along with the one or two fields the user has filled in. How can I check for the rows that have not been filled in and leave them out of the query? or check for those that have been filled in and add them to the query. . . The thank_you.php file will capture the $_POST variables and add them to the database. <form method="post" action="thank_you.php"> Name: <input type="text" size="28" name="name1" /> E-mail: <input type="text" size="28" name="email1" /> <br /> Name: <input type="text" size="28" name="name2" /> E-mail: <input type="text" size="28" name="email2" /> <br /> Name: <input type="text" size="28" name="name3" /> E-mail: <input type="text" size="28" name="email3" /> <br /> Name: <input type="text" size="28" name="name4" /> E-mail: <input type="text" size="28" name="email4" /> <input type="image" src="images/btn_s.jpg" /> </form> I am assuming that I could use javascript or jQuery to accomplish this, how would I go about doing this? Thanx in advance for the help.

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• Haskell Cons Operator (:)

  - by Carson Myers

  I am really new to Haskell (Actually I saw "Real World Haskell" from O'Reilly and thought "hmm, I think I'll learn functional programming" yesterday) and I am wondering: I can use the construct operator to add an item to the beginning of a list: 1 : [2,3] [1,2,3] I tried making an example data type I found in the book and then playing with it: --in a file data BillingInfo = CreditCard Int String String | CashOnDelivery | Invoice Int deriving (Show) --in ghci $ let order_list = [Invoice 2345] $ order_list [Invoice 2345] $ let order_list = CashOnDelivery : order_list $ order_list [CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, CashOnDelivery, ...- etc... it just repeats forever, is this because it uses lazy evaluation? -- EDIT -- okay, so it is being pounded into my head that let order_list = CashOnDelivery:order_list doesn't add CashOnDelivery to the original order_list and then set the result to order_list, but instead is recursive and creates an infinite list, forever adding CashOnDelivery to the beginning of itself. Of course now I remember that Haskell is a functional language and I can't change the value of the original order_list, so what should I do for a simple "tack this on to the end (or beginning, whatever) of this list?" Make a function which takes a list and BillingInfo as arguments, and then return a list? -- EDIT 2 -- well, based on all the answers I'm getting and the lack of being able to pass an object by reference and mutate variables (such as I'm used to)... I think that I have just asked this question prematurely and that I really need to delve further into the functional paradigm before I can expect to really understand the answers to my questions... I guess what i was looking for was how to write a function or something, taking a list and an item, and returning a list under the same name so the function could be called more than once, without changing the name every time (as if it was actually a program which would add actual orders to an order list, and the user wouldn't have to think of a new name for the list each time, but rather append an item to the same list).

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• How can I send GET data to multiple URLs at the same time using cURL?

  - by Rob

  My apologies, I've actually asked this question multiple times, but never quite understood the answers. Here is my current code: while($resultSet = mysql_fetch_array($SQL)){ $ch = curl_init($resultSet['url'] . $fullcurl); //load the urls and send GET data curl_setopt($ch, CURLOPT_TIMEOUT, 2); //Only load it for two seconds (Long enough to send the data) curl_exec($ch); //Execute the cURL curl_close($ch); //Close it off } //end while loop What I'm doing here, is taking URLs from a MySQL Database ($resultSet['url']), appending some extra variables to it, just some GET data ($fullcurl), and simply requesting the pages. This starts the script running on those pages, and that's all that this script needs to do, is start those scripts. It doesn't need to return any output. Just the load the page long enough for the script to start. However, currently it's loading each URL (currently 11) one at a time. I need to load all of them simultaneously. I understand I need to use curl_multi_*, but I haven't the slightest idea on how cURL functions work, so I don't know how to change my code to use curl_multi_* in a while loop. So my questions are: How can I change this code to load all of the URLs simultaneously? Please explain it and not just give me code. I want to know what each individual function does exactly. Will curl_multi_exec even work in a while loop, since the while loop is just sending each row one at a time? And of course, any references, guides, tutorials about cURL functions would be nice, as well. Preferably not so much from php.net, as while it does a good job of giving me the syntax, its just a little dry and not so good with the explanations.

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