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  • Retrieve the Value of An Integer Variable

    - by Abluescarab
    This is probably easily figured out (I feel very stupid right now), but I can't find a solution anywhere, for some reason. Perhaps I'm not searching for the right thing. And maybe it's in some beginner tutorial I haven't watched. Anyway, I was wondering how to retrieve the value of an integer variable in C++? I know you can use cin.getline() for string variables, but I received an error message when I attempted that with an integer variable (and rightfully so, I know it was wrong, but I was looking for a solution). My project is a Win32 console application. What I'm trying to do is ask a user to input a number, stored in the variable n. Then I take the value of n and perform various math functions with it. In my header file, I have string, windows, iostream, stdio, math, and fstream. Do I need to add another library? There's not much more to tell. I can post my code if I must. EDIT: cout << "TEST SINE"; cout << "\nPlease enter a number.\n\n"; cin >> n; break; Here's the code I'm trying to use. Is this all I need to do? If so, how do I incorporate the variable so I can test it using sin, cos, and tan? Yet again, thanks ahead of time.

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  • Unusual heap size limitations in VS2003 C++

    - by Shane MacLaughlin
    I have a C++ app that uses large arrays of data, and have noticed while testing that it is running out of memory, while there is still plenty of memory available. I have reduced the code to a sample test case as follows; void MemTest() { size_t Size = 500*1024*1024; // 512mb if (Size > _HEAP_MAXREQ) TRACE("Invalid Size"); void * mem = malloc(Size); if (mem == NULL) TRACE("allocation failed"); } If I create a new MFC project, include this function, and run it from InitInstance, it works fine in debug mode (memory allocated as expected), yet fails in release mode (malloc returns NULL). Single stepping through release into the C run times, my function gets inlined I get the following // malloc.c void * __cdecl _malloc_base (size_t size) { void *res = _nh_malloc_base(size, _newmode); RTCCALLBACK(_RTC_Allocate_hook, (res, size, 0)); return res; } Calling _nh_malloc_base void * __cdecl _nh_malloc_base (size_t size, int nhFlag) { void * pvReturn; // validate size if (size > _HEAP_MAXREQ) return NULL; ' ' And (size _HEAP_MAXREQ) returns true and hence my memory doesn't get allocated. Putting a watch on size comes back with the exptected 512MB, which suggests the program is linking into a different run-time library with a much smaller _HEAP_MAXREQ. Grepping the VC++ folders for _HEAP_MAXREQ shows the expected 0xFFFFFFE0, so I can't figure out what is happening here. Anyone know of any CRT changes or versions that would cause this problem, or am I missing something way more obvious?

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  • Goldbach theory in C

    - by nofe
    I want to write some code which takes any positive, even number (greater than 2) and gives me the smallest pair of primes that sum up to this number. I need this program to handle any integer up to 9 digits long. My aim is to make something that looks like this: Please enter a positive even integer ( greater than 2 ) : 10 The first primes adding : 3+7=10. Please enter a positive even integer ( greater than 2 ) : 160 The first primes adding : 3+157=160. Please enter a positive even integer ( greater than 2 ) : 18456 The first primes adding : 5+18451=18456. I don't want to use any library besides stdio.h. I don't want to use arrays, strings, or anything besides for the most basic toolbox: scanf, printf, for, while, do-while, if, else if, break, continue, and the basic operators (<,, ==, =+, !=, %, *, /, etc...). Please no other functions especially is_prime. I know how to limit the input to my needs so that it loops until given a valid entry. So now I'm trying to figure out the algorithm. I thought of starting a while loop like something like this: #include <stdio.h> long first, second, sum, goldbach, min; long a,b,i,k; //indices int main (){ while (1){ printf("Please enter a positive integer :\n"); scanf("%ld",&goldbach); if ((goldbach>2)&&((goldbach%2)==0)) break; else printf("Wrong input, "); } while (sum!=goldbach){ for (a=3;a<goldbach;a=(a+2)) for (i=2;(goldbach-a)%i;i++) first = a; for (b=5;b<goldbach;b=(b+2)) for (k=2;(goldbach-b)%k;k++) sum = first + second; } }

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  • Rewriting jQuery to plain old javascript - are the performance gains worth it?

    - by Swader
    Since jQuery is an incredibly easy and banal library, I've developed a rather complex project fairly quickly with it. The entire interface is jQuery based, and memory is cleaned regularly to maintain optimum performance. Everything works very well in Firefox, and exceptionally so in Chrome (other browsers are of no concern for me as this is not a commercial or publicly available product). What I'm wondering now is - since pure plain old javascript is really not a complicated language to master, would it be performance enhancing to rewrite the whole thing in plain old JS, and if so, how much of a boost would you expect to get from it? If the answers prove positive enough, I'll go ahead and do it, run a benchmark and report back with the precise findings. Cheers Edit: Thanks guys, valuable insight. The purpose was not to "re-invent the wheel" - it was just for experience and personal improvement. Just because something exists, doesn't mean you shouldn't explore it into greater detail, know how it works or try to recreate it. This is the same reason I seldom use frameworks, I would much rather use my own code and iron it out and gain massive experience doing it, than start off by using someone else's code, regardless of how ironed out it is. Anyway, won't be doing it, thanks for saving me the effort :)

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  • Get Image from Byte Aarray.

    - by Arun Thakkar
    Hello Everyone!! Hope You all are fine and also in one of your best of moods!! Hope You all are Enjoying iPhone development. I herewith one issue that i am not able to solve, may be i don't know the depth concept of iPhone. So Its my humble requet to you to guide me or suggest or share your ideas. I do find an issue with getting an image from Bytes array. I am calling a webservice which returns an image in form of Bytes Array as response. I have Converted this bytes array in to form of NSData, Now i have NSData, But When i Try to get an image from this NSData, It shows nil. I Did lots of R&D and Find one suggestion to use base64 encoder, But unfortunately because of not proper guidance I was not able to Implement that. I was also suggested to use OPenSSL Library for base64 from url http://www.cocoadev.com/index.pl?BaseSixtyFour But again i was not able to include #include #include these two files. as in Newer Version of SDK 3.X family Apple has depreciated those (as i guess). So Now i need help from you guys. kindly help me if you have solution or if you know the steps to solve these. Looking Forwards. Regards, Arun Thakkar

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  • JNI Stream binary data from C++ to Java

    - by Cliff
    I need help passing binary data into Java. I'm trying to use jbytearray but when the data gets into Java it appears corrupt. Can somebody give me a hand? Here's a snip of some example code. First the native C++ side: printf("Building audio array copy\n"); jbyteArray rawAudioCopy = env-NewByteArray(10); jbyte toCopy[10]; printf("Filling audio array copy\n"); char theBytes[10] = {0,1,2,3,4,5,6,7,8,9}; for (int i = 0; i < sizeof(theBytes); i++) { toCopy[i] = theBytes[i]; } env->SetByteArrayRegion(rawAudioCopy,0,10,toCopy); printf("Finding object callback\n"); jmethodID aMethodId = env->GetMethodID(env->GetObjectClass(obj),"handleAudio","([B)V"); if(0==aMethodId) throw MyRuntimeException("Method not found error",99); printf("Invoking the callback\n"); env->CallVoidMethod(obj,aMethodId, &rawAudioCopy); and then the Java callback method: public void handleAudio(byte[] audio){ System.out.println("Audio supplied to Java [" + audio.length + "] bytes"); byte[] expectedAudio = {0,1,2,3,4,5,6,7,8,9}; for (int i = 0; i < audio.length; i++) { if(audio[i]!= expectedAudio[i]) System.err.println("Expected byte " + expectedAudio[i] + " at byte " + i + " but got byte " + audio[i]); else System.out.print('.'); } System.out.println("Audio passed back accordingly!"); } I get the following output when the callback is invoked: library loaded! Audio supplied to Java [-2019659176] bytes Audio passed back accordingly!

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  • Why there is no scoped locks for multiple mutexes in C++0x or Boost.Thread?

    - by Vicente Botet Escriba
    C++0x thread library or Boost.thread define non-member variadic template function that lock all lock avoiding dead lock. template <class L1, class L2, class... L3> void lock(L1&, L2&, L3&...); While this function avoid help to deadlock, the standard do not includes the associated scoped lock to write exception safe code. { std::lock(l1,l2); // do some thing // unlock li l2 exception safe } That means that we need to use other mechanism as try-catch block to make exception safe code or define our own scoped lock on multiple mutexes ourselves or even do that { std::lock(l1,l2); std::unique_lock lk1(l1, std::adopted); std::unique_lock lk2(l2, std::adopted); // do some thing // unlock li l2 on destruction of lk1 lk2 } Why the standard doesn't includes a scoped lock on multiple mutexes of the same type, as for example { std::array_unique_lock<std::mutex> lk(l1,l2); // do some thing // unlock l1 l2 on destruction of lk } or tuples of mutexes { std::tuple_unique_lock<std::mutex, std::recursive_mutex> lk(l1,l2); // do some thing // unlock l1 l2 on destruction of lk } Is there something wrong on the design?

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  • C# generics when T could be an array

    - by bufferz
    I am writing a C# wrapper for a 3rd party library that reads both single values and arrays from a hardware device, but always returns an object[] array even for one value. This requires repeated calls to object[0] when I'd like the end user to be able to use generics to receive either an array or single value. I want to use generics so the callee can use the wrapper in the following ways: MyWrapper<float> mw = new MyWrapper<float>( ... ); float value = mw.Value; //should return float; MyWrapper<float[]> mw = new MyWrapper<float[]>( ... ); float[] values = mw.Value; //should return float[]; In MyWrapper I have the Value property currently as the following: public T Value { get { if(_wrappedObject.Values.Length > 1) return (T)_wrappedObject.Value; //T could be float[]. this doesn't compile. else return (T)_wrappedObject.Values[0]; //T could be float. this compiles. } } I get a compile error in the first case: Cannot convert type 'object[]' to 'T' If I change MyWrapper.Value to T[] I receive: Cannot convert type 'object[]' to 'T[]' Any ideas of how to achieve my goal? Thanks!

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  • Generating a canonical path

    - by Joel
    Does any one know of any Java libraries I could use to generate canonical paths (basically remove back-references). I need something that will do the following: Raw Path - Canonical Path /../foo/ -> /foo /foo/ -> /foo /../../../ -> / /./foo/./ -> /foo //foo//bar -> /foo/bar //foo/../bar -> /bar etc... At the moment I lazily rely on using: new File("/", path).getCanonicalPath(); But this resolves the path against the actual file system, and is synchronised. java.lang.Thread.State: BLOCKED (on object monitor) at java.io.ExpiringCache.get(ExpiringCache.java:55) - waiting to lock <0x93a0d180> (a java.io.ExpiringCache) at java.io.UnixFileSystem.canonicalize(UnixFileSystem.java:137) at java.io.File.getCanonicalPath(File.java:559) The paths that I am canonicalising do not exist on my file system, so just the logic of the method will do me fine, thus not requiring any synchronisation. I'm hoping for a well tested library rather than having to write my own.

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  • Java plugin framework choice

    - by Marcus
    We're trying to determine how to implement a simple plugin framework for a service we are implementing that allows different types of calculators to be "plugged-in". After reading a number of posts about Java plugin frameworks, it seems like the most common options are: OSGI "Rolling your own" plugin framework The Java Plugin Framework (JPF) The Java Simple Plugin Framework (JSPF) OSGI seems to be more than we need. "Rolling your own" is ok but it would be nice to reuse a common library. So we're down to the JPF and JSPF. JPF seems to not be in active development right now. JSPF seems very simple and really all we need. However I haven't heard much about it. I've only seen one post on StackOverflow about it. Does anyone else have any experience with JSPF? Or any other comments on this design choice? Update: There isn't necessarily a correct answer to this.. however we're going to go with Pavol's idea as we need just a really, really simple solution. Thanks EoH for the nice guide.

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  • Where does java.util.logging.Logger store their log

    - by Harry Pham
    This might be a stupid question but I am a bit lost with java Logger private static Logger logger = Logger.getLogger("order.web.OrderManager"); logger.info("Removed order " + id + "."); Where do I see the log? Also this quote from java.util.logging.Logger library: On each logging call the Logger initially performs a cheap check of the request level (e.g. SEVERE or FINE) against the effective log level of the logger. If the request level is lower than the log level, the logging call returns immediately. After passing this initial (cheap) test, the Logger will allocate a LogRecord to describe the logging message. It will then call a Filter (if present) to do a more detailed check on whether the record should be published. If that passes it will then publish the LogRecord to its output Handlers. Does this mean that if I have 3 request level log: logger.log(Level.FINE, "Something"); logger.log(Level.WARNING, "Something"); logger.log(Level.SEVERE, "Something"); And my log level is SEVERE, I can see all three logs, if my log level is WARNING, then I cant see SEVERE log, is that correct? And how do I set the log level?

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  • Overriding Code Igniter 2.14's global_xss_filtering settting

    - by user2353007
    I have created the following file at: application/core/MY_Security.php <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); /* * Does not work with global xss */ class MY_Security extends CI_Security { function xss_clean($str, $is_image = FALSE) { $CI =& get_instance(); $CI->load->library('My_cleaner'); return $CI->my_cleaner->clean_html($str); } } this works great for $this-input-post('post_var', TRUE); and $this-security-xss_clean($input); It is working very well except when I go into application/config/config.php and change $config['global_xss_filtering] = FALSE; to $config['global_xss_filtering] = TRUE; in that case, I just get a white page on every controllers action/function. Does anybody know what else I have to change to get global_xss_filtering = TRUE; to work when overriding the xss_clean function in system/core/Security.php through application/core/MY_Security.php? I'm guessing it might be something with the loader but I'm not sure where to start. The next option is to just replace the function in the system/core/Security.php file which I am trying to avoid. Thanks.

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  • MySQLPython is ignoring my my.cnf file. Where does it get its information?

    - by ?????
    When I try to use MySQLPython (via SQLAlchemy) I get the error File "/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/MySQL_python-1.2.3c1-py2.6-macosx-10.6-x86_64.egg/MySQLdb/connections.py", line 188, in __init__ super(Connection, self).__init__(*args, **kwargs2) sqlalchemy.exc.OperationalError: (OperationalError) (2002, "Can't connect to local MySQL server through socket '/opt/local/var/run/mysql5/mysqld.sock' (2)") None None but no other mysql client on my machine sees it fine! My my.cnf file states: [client] port = 3306 socket = /tmp/mysql/mysql.sock [safe_mysqld] socket = /tmp/mysql/mysql.sock [mysqld_safe] socket = /tmp/mysql/mysql.sock [mysqld] socket = /tmp/mysql/mysql.sock port = 3306 and the mysql.sock file is, indeed, located in /tmp/mysql I verified that ~/.my.cnf and /var/lib/mysql/my.cnf aren't overriding it. The mysql5 client program, etc, has no trouble connecting and neither does a groovy/grails installation on the same machine using jdbc/mysql connection thrilllap-2:~ swirsky$ mysql5 Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 6 Server version: 5.1.47 Source distribution Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. This software comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to modify and redistribute it under the GPL v2 license Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | test | +--------------------+ 2 rows in set (0.00 sec) mysql> Why can't MySQLdb for python figure this out? Where would it look if not the my.cnf files?

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  • Problem with NSString

    - by Kassar
    I have a problem with NSString in dynamic binding ... I manipulate with Facebook library, when i'll share my story i should make an instance of FBStreamDialog and charge its attributes with values of the story then show it, like this: FBStreamDialog* dialog = [[[FBStreamDialog alloc] init]autorelease]; dialog.delegate = self; dialog.userMessagePrompt = @"prompt"; NSString* sss=@"{ \"name\":\"%@\", \"href\":\"%@\", \"caption\":\"%@\", \"description\":\"%@\" , \"media\":[{ \"type\":\"image\", \"src\":\"%@\", \"href\":\"%@\" }] }"; dialog.attachment = [NSString stringWithFormat:sss,@"title",@"http://www.docs.com/hi.html",@"caption",@"summary",@"http://www.images.com/206.jpg",@"http://www.images.com/206.jpg"]; NSLog(@"ATTACHMENT: %@",dialog.attachment); The code above is running well. But my problem is when i want to charge these attributes dynamically like this: BStreamDialog* dialog = [[[FBStreamDialog alloc] init]autorelease]; dialog.delegate = self; dialog.userMessagePrompt = @"prompt"; NSString* sss=@"{ \"name\":\"%@\", \"href\":\"%@\", \"caption\":\"%@\", \"description\":\"%@\" , \"media\":[{ \"type\":\"image\", \"src\":\"%@\", \"href\":\"%@\" }] }"; dialog.attachment = [NSString stringWithFormat:sss,story.title,story.link,story.caption,story.summary,story.imagelink,story.imagelink]; NSLog(@"ATTACHMENT: %@",dialog.attachment); It's running without crash but it doesn't share the story it share a blank one !!! Although, it shows in the console (output of NSLog) the value of attachment is true !!! Could you plz help me. Sorry for my english.

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  • How can I invoke a .Net DLL from a LabView 6.1 VI?

    - by tw1k
    I work in a manufacturing company that uses LabView for testing the devices we make. Most of the test engineers are using 7.1 which can natively reference a .Net assembly. However, there is a group that is stuck on LabView 6.1. I would like for them to be able to use my .Net assembly which is basically a proxy to some web services. I have created a test assembly that is nothing more than Hello World, and I'm trying to consume it in a VI. I made it COM visible, and registered it with regasm.exe and created a type library, which I'm not sure I need. I can see it in Visual Studio in the list of COM objects when I open the Add Reference window, so I know it's registered properly. I'm very unfamiliar with VI's. I'm only looking at it because no one I have spoken to in manufacturing knows anything about invoking a COM object in a VI. I'm basically looking for some names of controls or menu options to get the test engineers pointed in the right direction. I did a bunch of web searching on Google and the NI forums, but didn't find much. Alternatively, would it be easier to write a C or C++ DLL that acts as a proxy to my .Net DLL? Or is there a simple way to invoke a web service from a VI? That might obviate the need for a DLL altogether. I'm currently reading through this document from NI for help, but it obviously knows nothing about .Net and might not be able to help me choose the best path forward.

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  • Codeigniter achor producing dodgy link in email inbox.. what could the problem be?

    - by Psychonetics
    My application is emailing out fine but the email I receive displays incorrectly. Rather than have text and a simple "click here to activate" link it doesn't. it shows this instead: Hi user1, please click the following link to activate your account <a href="http://mysite.com/activation/fzyZuyxVAzZS2koVg5UFjfVjlcLNcrzp">ssss</a> Here is the code from my model that sends email to user when they request activation email. $this->load->library('email'); $this->email->from('[email protected]', 'my site'); $this->email->to($result[0]->email); $this->email->subject('my site - Activate your account'); $this->email->message('Hi ' . $result[0]->first_name . ', please click the following link to activate your account ' . anchor('http://mysite.com/activation/' . $new_activation_code, 'click here to activate')); $this->email->send(); Also the mail always ends up in my spam folder.

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  • Static Variables somehow maintaining state?

    - by gfoley
    I am working on an existing project, setup by another coder. I'm having some trouble understanding how state is being maintained between pages. There is a Class library which has some helper objects. Mostly these objects are just used for there static methods and rarely instantiated or inherited. This is an example class I'm testing with. public sealed class Application { public static string Test; } Now when i run something like the following in the base class of my page, I would expect the result to be "1: 2:Test" all the time (note that "1" is empty), but strangly its only this way the first time it is run. Then every time afterwards its "1:Test 2:Test". Somehow its maintaining the state of the static variable between pages and being refreshed?? Response.Write("1:" + SharedLibrary.Application.Test); SharedLibrary.Application.Test = "Test"; Response.Write(" 2:" + SharedLibrary.Application.Test); I need to create more classes like this, but want to understand why this is occurring in the first place. Many Thanks

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  • Boost's "cstdint" Usage

    - by patt0h
    Boost's C99 stdint implementation is awfully handy. One thing bugs me, though. They dump all of their typedefs into the boost namespace. This leaves me with three choices when using this facility: Use "using namespace boost" Use "using boost::[u]<type><width>_t" Explicitly refer to the target type with the boost:: prefix; e.g., boost::uint32_t foo = 0; Option ? 1 kind of defeats the point of namespaces. Even if used within local scope (e.g., within a function), things like function arguments still have to be prefixed like option ? 3. Option ? 2 is better, but there are a bunch of these types, so it can get noisy. Option ? 3 adds an extreme level of noise; the boost:: prefix is often = to the length of the type in question. My question is: What would be the most elegant way to bring all of these types into the global namespace? Should I just write a wrapper around boost/cstdint.hpp that utilizes option ? 2 and be done with it? Also, wrapping the header like so didn't work on VC++ 10 (problems with standard library headers): namespace Foo { #include <boost/cstdint.hpp> using namespace boost; } using namespace Foo; Even if it did work, I guess it would cause ambiguity problems with the ::boost namespace.

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  • Java-Hibernate: How can I translate these tables to hibernate annotations?

    - by penas
    I need to create a simple application using these tables: http://stackoverflow.com/questions/2612848/are-these-tables-respect-the-3nf-database-normalization I have created the application using simple old JDBC, but I would like to see how the application would look like using Hibernate, but I don't know how to put the sql code in java. I have found LOTS of examples, but I'm pretty much confused about using Hibernate and I don't know If I made such a good joob. For example, for the first three tables: AUTHOR table * Author_ID, PK * First_Name * Last_Name TITLES table * TITLE_ID, PK * NAME * Author_ID, FK DOMAIN table * DOMAIN_ID, PK * NAME * TITLE_ID, FK The code in java: Table 1 @Entity @Table(name = "AUTHORS", schema = "LIBRARY") public class Author{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "Author_ID") private int authorId; @Column(name = "First_Name", nullable = false, length = 50) private String firstName; @Column(name = "Last_Name", nullable = false, length = 40) private String lastName; @OneToMany @JoinColumn(name = "Title_ID") private List<Title> titles; Table 2 @Entity @Table(name = "TITLES") public class Title{ @Id @Column(name = "Title_ID") private int titleID; @Column(name = "Name", nullable = false, length = 50) private String name; @ManyToOne @JoinColumn(name = "Domain_ID") private Domain domains; Table 3 @Entity @Table(name = "DOMAINS") public class Domain{ @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name = "Domain_ID") private int Domain_ID; @Column(name = "Name", nullable = false, length = 50) private String name; @OneToOne(mappedBy = "domains") private Title title; } Any good? :)

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  • Accents in uploaded file being replaced with '?'

    - by Katfish
    I am building a data import tool for the admin section of a website I am working on. The data is in both French and English, and contains many accented characters. Whenever I attempt to upload a file, parse the data, and store it in my MySQL database, the accents are replaced with '?'. I have text files containing data (charset is iso-8859-1) which I upload to my server using CodeIgniter's file upload library. I then read the file in PHP. My code is similar to this: $this->upload->do_upload() $data = array('upload_data' => $this->upload->data()); $fileHandle = fopen($data['upload_data']['full_path'], "r"); while (($line = fgets($fileHandle)) !== false) { echo $line; } This produces lines with accents replaced with '?'. Everything else is correct. If I download my uploaded file from my server over FTP, the charset is still iso-8850-1, but a diff reveals that the file has changed. However, if I open the file in TextEdit, it displays properly. I attempted to use PHP's stream_encoding method to explicitly set my file stream to iso-8859-1, but my build of PHP does not have the method. After running out of ideas, I tried wrapping my strings in both utf8_encode and utf8_decode. Neither worked. If anyone has any suggestions about things I could try, I would be extremely grateful.

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  • Best Practice: Access form elements by HTML id or name attribute?

    - by seth
    As any seasoned JavaScript developer knows, there are many (too many) ways to do the same thing. For example, say you have a text field as follows: <form name="myForm"> <input type="text" name="foo" id="foo" /> There are many way to access this in JavaScript: [1] document.forms[0].elements[0]; [2] document.myForm.foo; [3] document.getElementById('foo'); [4] document.getElementById('myForm').foo; ... and so on ... Methods [1] and [3] are well documented in the Mozilla Gecko documentation, but neither are ideal. [1] is just too general to be useful and [3] requires both an id and a name (assuming you will be posting the data to a server side language). Ideally, it would be best to have only an id attribute or a name attribute (having both is somewhat redundant, especially if the id isn't necessary for any css, and increases the likelihood of typos, etc). [2] seems to be the most intuitive and it seems to be widely used, but I haven't seen it referenced in the Gecko documentation and I'm worried about both forwards compatibility and cross browser compatiblity (and of course I want to be as standards compliant as possible). So what's best practice here? Can anyone point to something in the DOM documentation or W3C specification that could resolve this? Note I am specifically interested in a non-library solution (jQuery/Prototype).

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  • form:select items problem in spring mvc portlet

    - by dhaval
    I have a set of drop-down control which I want to render with my custom tag library. The following is the code of the tag lib: <spring:bind path="${path}"> <c:choose> <c:when test="${readOnly}"> <span class="readOnly">${status.value}</span> </c:when> <c:otherwise> <form:select path="${path }" itemLabel="${label }" itemValue="${value }" items="${itemList}"> </form:select> </c:otherwise> </c:choose> And this is the code I have written in the JSP file: <tag:conditionalListControl path="model.selectedCountry" readOnly="false" label="name" value="id" listItems="model.countryList" className="simple" /> Upon execution the paring returns the following error: [jsp:165] javax.servlet.jsp.JspException: Type [java.lang.String] is not valid for option items But if i change the items="${itemList}" to items="${model.countryList}" which is the list I want to display, it works fine without any problem and also bind to required variables on form submit. But i don't want to hard code any variables in the tag lib. Any suggestions???

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  • Faster quadrature decoder loops with Python code

    - by Kelei
    I'm working with a BeagleBone Black and using Adafruit's IO Python library. Wrote a simple quadrature decoding function and it works perfectly fine when the motor runs at about 1800 RPM. But when the motor runs at higher speeds, the code starts missing some of the interrupts and the encoder counts start to accumulate errors. Do you guys have any suggestions as to how I can make the code more efficient or if there are functions which can cycle the interrupts at a higher frequency. Thanks, Kel Here's the code: # Define encoder count function def encodercount(term): global counts global Encoder_A global Encoder_A_old global Encoder_B global Encoder_B_old global error Encoder_A = GPIO.input('P8_7') # stores the value of the encoders at time of interrupt Encoder_B = GPIO.input('P8_8') if Encoder_A == Encoder_A_old and Encoder_B == Encoder_B_old: # this will be an error error += 1 print 'Error count is %s' %error elif (Encoder_A == 1 and Encoder_B_old == 0) or (Encoder_A == 0 and Encoder_B_old == 1): # this will be clockwise rotation counts += 1 print 'Encoder count is %s' %counts print 'AB is %s %s' % (Encoder_A, Encoder_B) elif (Encoder_A == 1 and Encoder_B_old == 1) or (Encoder_A == 0 and Encoder_B_old == 0): # this will be counter-clockwise rotation counts -= 1 print 'Encoder count is %s' %counts print 'AB is %s %s' % (Encoder_A, Encoder_B) else: #this will be an error as well error += 1 print 'Error count is %s' %error Encoder_A_old = Encoder_A # store the current encoder values as old values to be used as comparison in the next loop Encoder_B_old = Encoder_B # Initialize the interrupts - these trigger on the both the rising and falling GPIO.add_event_detect('P8_7', GPIO.BOTH, callback = encodercount) # Encoder A GPIO.add_event_detect('P8_8', GPIO.BOTH, callback = encodercount) # Encoder B # This is the part of the code which runs normally in the background while True: time.sleep(1)

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  • Simplification / optimization of GPS track

    - by GreyCat
    I've got a GPS track, produces by gpxlogger(1) (supplied as a client for gpsd). GPS receiver updates its coordinates every 1 second, gpxlogger's logic is very simple, it writes down location (lat, lon, ele) and a timestamp (time) received from GPS every n seconds (n = 3 in my case). After writing down a several hours worth of track, gpxlogger saves several megabyte long GPX file that includes several thousands of points. Afterwards, I try to plot this track on a map and use it with OpenLayers. It works, but several thousands of points make using the map a sloppy and slow experience. I understand that having several thousands of points of suboptimal. There are myriads of points that can be deleted without losing almost anything: when there are several points making up roughly the straight line and we're moving with the same constant speed between them, we can just leave the first and the last point and throw anything else. I thought of using gpsbabel for such track simplification / optimization job, but, alas, it's simplification filter works only with routes, i.e. analyzing only geometrical shape of path, without timestamps (i.e. not checking that the speed was roughly constant). Is there some ready-made utility / library / algorithm available to optimize tracks? Or may be I'm missing some clever option with gpsbabel?

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  • How to fix Java Image Fetcher error ?

    - by Frank
    My code looks like this : private static JFileChooser fc; if (fc==null) { fc=new JFileChooser(Image_Dir); fc.addChoosableFileFilter(new Image_Filter()); // Add a custom file filter and disable the default (Accept All) file filter. fc.setAcceptAllFileFilterUsed(false); fc.setAccessory(new Image_Preview(fc)); // Add the preview pane. } int returnVal=fc.showDialog(JFileChooser_For_Image.this,"Get Image"); // Show it. After I select an image from the panel, I got the following error message : Exception in thread "Image Fetcher 0" java.lang.UnsatisfiedLinkError: Native Library C:\Program Files (x86)\Java\jre6\bin\jpeg.dll already loaded in another classloader at java.lang.ClassLoader.loadLibrary0(Unknown Source) at java.lang.ClassLoader.loadLibrary(Unknown Source) at java.lang.Runtime.loadLibrary0(Unknown Source) at java.lang.System.loadLibrary(Unknown Source) at sun.security.action.LoadLibraryAction.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at sun.awt.image.JPEGImageDecoder.<clinit>(Unknown Source) at sun.awt.image.InputStreamImageSource.getDecoder(Unknown Source) at sun.awt.image.FileImageSource.getDecoder(Unknown Source) at sun.awt.image.InputStreamImageSource.doFetch(Unknown Source) at sun.awt.image.ImageFetcher.fetchloop(Unknown Source) at sun.awt.image.ImageFetcher.run(Unknown Source) When I run it from an executable Jar file, it works fine, but after I wrapped it into an exe file, I got the above error, why ? How to fix it ?

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