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  • jQuery Validation plugin: checkbox groups and error message issues

    - by boomturn
    I've put together a form using the jQuery Validation plugin, and all inputs are fine with working validation and error messages – except for checkboxes. I have two checkbox problems. The first is that the Validation plugin API doesn't seem to handle checkboxes in grouped contexts (I'm using fieldsets for grouping). Found several approaches to the issue here, including reference to a post by Rebecca Murphey for a more general case using a custom method and class. Adapting that to this situation: jQuery.validator.addMethod('required_group', function(val, el) { var fieldParent = $(el).closest('fieldset'); return fieldParent.find('.required_group:checked').length; }); jQuery.validator.addClassRules('required_group', { 'required_group': true }); jQuery.validator.messages.required_group = 'Please check at least one box.'; This sort of works, but produces error messages on every checkbox, and only removes them as each box is clicked. This is not an acceptable situation for the user, who can only get rid of them by clicking false positives. Ideally, I guess what's needed is something to prevent or eliminate extra messages before they are displayed and use errorPlacement to display a single error message in the parent fieldset, that would then be removed with a click on any checkbox. Less ideally, maybe they would all display but an event handler could turn off the full set of redundant messages with a click, which is what this approach offered by tvanfosson appears to do. (Another customized approach here, but I couldn't get it to work.) I guess I should also note this form requires the checkboxes to have different names. My second problem is that one of the fieldsets with checkboxes in the form also contains a nested fieldset of checkboxes under one of the outer checkboxes. So in addition to the first-level one-box-checked requirement, if the particular checkbox containing the second-level checkboxes is checked, then at least one of the second-level boxes must be checked. Not sure about the right approach; I'm guessing what needs to happen (following the above scheme) is that the trigger checkbox would use toggleClass to add/remove 'required_group' class to all the checkboxes in the subfield, which would then (hopefully) behave the same as the parent field: $("#triggerCheckbox").click(function () { $(this).find(":checkbox").toggleClass("required_group"); }); Any suggestions or ideas welcome. I'm well beyond my limited jQuery skills on this one and would be happy to hear that I missed simple, elegant and/or obvious ways to do this!

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  • Finding what makes strings unique in a list, can you improve on brute force?

    - by Ed Guiness
    Suppose I have a list of strings where each string is exactly 4 characters long and unique within the list. For each of these strings I want to identify the position of the characters within the string that make the string unique. So for a list of three strings abcd abcc bbcb For the first string I want to identify the character in 4th position d since d does not appear in the 4th position in any other string. For the second string I want to identify the character in 4th position c. For the third string it I want to identify the character in 1st position b AND the character in 4th position, also b. This could be concisely represented as abcd -> ...d abcc -> ...c bbcb -> b..b If you consider the same problem but with a list of binary numbers 0101 0011 1111 Then the result I want would be 0101 -> ..0. 0011 -> .0.. 1111 -> 1... Staying with the binary theme I can use XOR to identify which bits are unique within two binary numbers since 0101 ^ 0011 = 0110 which I can interpret as meaning that in this case the 2nd and 3rd bits (reading left to right) are unique between these two binary numbers. This technique might be a red herring unless somehow it can be extended to the larger list. A brute-force approach would be to look at each string in turn, and for each string to iterate through vertical slices of the remainder of the strings in the list. So for the list abcd abcc bbcb I would start with abcd and iterate through vertical slices of abcc bbcb where these vertical slices would be a | b | c | c b | b | c | b or in list form, "ab", "bb", "cc", "cb". This would result in four comparisons a : ab -> . (a is not unique) b : bb -> . (b is not unique) c : cc -> . (c is not unique) d : cb -> d (d is unique) or concisely abcd -> ...d Maybe it's wishful thinking, but I have a feeling that there should be an elegant and general solution that would apply to an arbitrarily large list of strings (or binary numbers). But if there is I haven't yet been able to see it. I hope to use this algorithm to to derive minimal signatures from a collection of unique images (bitmaps) in order to efficiently identify those images at a future time. If future efficiency wasn't a concern I would use a simple hash of each image. Can you improve on brute force?

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  • Optimizing spacing of mesh containing a given set of points

    - by Feynman
    I tried to summarize the this as best as possible in the title. I am writing an initial value problem solver in the most general way possible. I start with an arbitrary number of initial values at arbitrary locations (inside a boundary.) The first part of my program creates a mesh/grid (I am not sure which is the correct nuance), with N points total, that contains all the initial values. My goal is to optimize the mesh such that the spacing is as uniform as possible. My solver seems to work half decently (it needs some more obscure debugging that is not relevant here.) I am starting with one dimension. I intend to generalize the algorithm to an arbitrary number of dimensions once I get it working consistently. I am writing my code in fortran, but feel free to reply with pseudocode or the language of your choice. Allow me to elaborate with an example: Say I am working on a closed interval [1,10] xmin=1 xmax=10 Say I have 3 initial points: xmin, 5 and xmax num_ivc=3 known(num_ivc)=[xmin,5,xmax] //my arrays start at 1. Assume "known" starts sorted I store my mesh/grid points in an array called coord. Say I want 10 points total in my mesh/grid. N=10 coord(10) Remember, all this is arbitrary--except the variable names of course. The algorithm should set coord to {1,2,3,4,5,6,7,8,9,10} Now for a less trivial example: num_ivc=3 known(num_ivc)=[xmin,5.5,xmax or just num_ivc=1 known(num_ivc)=[5.5] Now, would you have 5 evenly spaced points on the interval [1, 5.5] and 5 evenly spaced points on the interval (5.5, 10]? But there is more space between 1 and 5.5 than between 5.5 and 10. So would you have 6 points on [1, 5.5] followed by 4 on (5.5 to 10]. The key is to minimize the difference in spacing. I have been working on this for 2 days straight and I can assure you it is a lot trickier than it sounds. I have written code that only works if N is large only works if N is small only works if it the known points are close together only works if it the known points are far apart only works if at least one of the known points is near a boundary only works if none of the known points are near a boundary So as you can see, I have coded the gamut of almost-solutions. I cannot figure out a way to get it to perform equally well in all possible scenarios (that is, create the optimum spacing.)

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  • How to best integrate generated code

    - by Arne
    I am evaluating the use of code generation for my flight simulation project. More specifically there is a requirement to allow "the average engineer" (no offense I am one myself) to define the differential equations that describe the dynamic system in a more natural syntax than C++ provides. The idea is to devise a abstract descriptor language that can be easily understood and edited to generate C++ code from. This descriptor is supplied by the modeling engineer and used by the ones implementing and maintaining the simulation evironment to generate code. I've got something like this in mind: model Aircraft has state x1, x2; state x3; input double : u; input bool : flag1, flag2; algebraic double : x1x2; model Engine : tw1, tw2; model Gear : gear; model ISA : isa; trim routine HorizontalFight; trim routine OnGround, General; constant double : c1, c2; constant int : ci1; begin differential equations x1' = x1 + 2.*x2; x2' = x2 + x1x2; begin algebraic equations x1x2 = x1*x2 + x1'; end model It is important to retain the flexibility of the C language thus the descriptor language is meant to only define certain parts of the definition and implementation of the model class. This way one enigneer provides the model in from of the descriptor language as examplified above and the maintenance enigneer will add all the code to read parameters from files, start/stop/pause the execution of the simulation and how a concrete object gets instatiated. My first though is to either generate two files from the descriptor file: one .h file containing declarations and one .cpp file containing the implementation of certain functions. These then need to be #included at appropriate places [File Aircarft.h] class Aircraft { public: void Aircraft(..); // hand-written constructor void ReadParameters(string &file_name); // hand-written private: /* more hand wirtten boiler-plate code */ /* generate declarations follow */ #include "Aircraft.generated.decl" }; [File Aircraft.cpp] Aircarft::Aircraft(..) { /* hand-written constructer implementation */ } /* more hand-written implementation code */ /* generated implementation code follows */ #include "Aircraft.generated.impl" Any thoughts or suggestions?

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  • [NSIS] Custom radio-buttom INI page via Eclipse

    - by Omegazero
    I'm using Eclipse's create InstallOptions menu to create a custom INI page with radio-buttons for repackaging the Blackberry Desktop installer. There are 2 sections for each type: "Internet" and "Enterprise". I need a user to select 1 of the 2 options and depending on their selection, the page will carry over the selection chosen in the custom page, jump to the INSTFILES page, and continue onto the end. I couldn't find any concrete documentation on getting INI pages to load in the script (I'm probably searching incorrectly), and then pass data from one page to the next (according to fields I guess?) Any help is appreciated. Even if it's to tell me I'm blind and can't read a doc (though a link would help :) ) Here's the INI code: ; Auto-generated by EclipseNSIS InstallOptions Script Wizard ; Jul 29, 2009 5:42:56 PM [Settings] NumFields=7 Title=RIM BlackBerry Desktop 5.0 installation CancelEnabled=1 [Field 1] Type=RadioButton Left=15 Top=28 Right=100 Bottom=38 Text=Internet State= Flags=NOTIFY [Field 4] Type=RadioButton Left=15 Top=95 Right=100 Bottom=105 Text=Enterprise Flags=NOTIFY [Field 2] Type=GroupBox Left=0 Top=10 Right=300 Bottom=75 Text= [Field 5] Type=Label Left=30 Top=42 Right=235 Bottom=52 Text=For users who are NOT on the Enterprise (Exchange) server [Field 6] Type=Label Left=30 Top=111 Right=235 Bottom=121 Text=Choose this only if you are on the Exchange server [Field 3] Type=GroupBox Left=0 Top=75 Right=300 Bottom=140 [Field 7] Type=Label Left=0 Top=0 Right=130 Bottom=10 Text=Please choose your installation method ...And here's the NSI code: Auto-generated by EclipseNSIS Script Wizard Jul 29, 2009 5:42:16 PM Name "BlackBerry Desktop" RequestExecutionLevel admin General Symbol Definitions !define VERSION 5.0.0.11 !define COMPANY RIM !define URL http://www.blackberry.com MUI Symbol Definitions !define MUI_ICON BBD.ico !define MUI_LICENSEPAGE_RADIOBUTTONS Included files !include Sections.nsh !include MUI2.nsh Reserved Files ReserveFile "${NSISDIR}\Plugins\AdvSplash.dll" Installer pages !insertmacro MUI_PAGE_WELCOME !insertmacro MUI_PAGE_LICENSE license.txt !insertmacro MUI_PAGE_COMPONENTS !insertmacro MUI_PAGE_INSTFILES !insertmacro MUI_PAGE_FINISH Installer languages !insertmacro MUI_LANGUAGE English Installer attributes OutFile RIM_BlackBerry_Desktop_5.0.exe InstallDir "$TEMP\RIM BlackBerry Desktop 5.0 Setup Files" CRCCheck on XPStyle on ShowInstDetails hide VIProductVersion 5.0.0.11 VIAddVersionKey /LANG=${LANG_ENGLISH} ProductName "BlackBerry Desktop" VIAddVersionKey /LANG=${LANG_ENGLISH} ProductVersion "${VERSION}" VIAddVersionKey /LANG=${LANG_ENGLISH} CompanyName "${COMPANY}" VIAddVersionKey /LANG=${LANG_ENGLISH} CompanyWebsite "${URL}" VIAddVersionKey /LANG=${LANG_ENGLISH} FileVersion "${VERSION}" VIAddVersionKey /LANG=${LANG_ENGLISH} FileDescription "" VIAddVersionKey /LANG=${LANG_ENGLISH} LegalCopyright "" Installer sections Section /o Main SEC0000 SetOutPath $INSTDIR SetOverwrite ifdiff ; TESTING PHASE SectionEnd SectionGroup /e "BlackBerry Desktop Section" Section /o Internet SEC0001 SetOutPath $INSTDIR\DRIVERS SetOverwrite ifdiff ; Execwait 'msiexec /i "$INSTDIR\BlackBerry USB and Modem Drivers_ENG (DM5.0b28).msi" /passive' SetOutPath $INSTDIR SetOverwrite ifdiff ; File /r * ; ExecWait '"$INSTDIR\Setup.exe" /S/v/qb!' SectionEnd Section /o Enterprise SEC0002 SetOutPath $INSTDIR\DRIVERS SetOverwrite ifdiff ; Execwait 'msiexec /i "$INSTDIR\BlackBerry USB and Modem Drivers_ENG (DM5.0b28).msi" /passive' SetOutPath $INSTDIR SetOverwrite ifdiff ; File /r * ; Delete /REBOOTOK "$INSTDIR\Setup.ini" ; Rename /REBOOTOK "$INSTDIR\Setup_Enterprise.ini" "$INSTDIR\Setup.ini" ; ExecWait '"$INSTDIR\Setup.exe" /S/v/qb!' SectionEnd SectionGroupEnd Section Descriptions !insertmacro MUI_FUNCTION_DESCRIPTION_BEGIN !insertmacro MUI_DESCRIPTION_TEXT ${SEC0000} $(SEC0000_DESC) !insertmacro MUI_DESCRIPTION_TEXT ${SEC0001} $(SEC0001_DESC) !insertmacro MUI_FUNCTION_DESCRIPTION_END Installer Language Strings TODO Update the Language Strings with the appropriate translations. LangString SEC0000_DESC ${LANG_ENGLISH} "Installation for non-Exchange/Enterprise BlackBerry Users" LangString SEC0001_DESC ${LANG_ENGLISH} "Installation for Exchange/Enterprise BlackBerry Users"

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  • ServiceController.Stop() doesn't appear to be stopping anything

    - by peacedog
    My dev box is a Windows 7 (x64) machine. I've got some code (C#, .net 2.0) that in certain circumstances, checks to see if a service is running and then stops it. ServiceController matchedService = //My Service! //If statements and such matchedService.Stop(); matchedService.WaitForStatus(ServiceControllerStatus.Stopped); Now, I can verify MyService is in fact installed and running. I can tell you I am running Visual Studio 2008 as an administrator while debugging. I can also verify that after a couple of If statements, I wind up at the .Stop() and .WaitForStatus() portion of the programming. I do know that if step over the .Stop() call, the service itself just keeps running (looking at it in Services, though it occurs to me perhaps I should grab a better tool for this. I'm sure there's some sysinternals tool that might give me more information). As I step over the .WaitForStatus() call, I basically wind up waiting for the stopped status. . . forever. Well, I let it sit there for over 15 minutes yesterday (twice) and nothing happens. We never make it to the next line of code. It feels exactly like Bowie's Space Oddity (you know the part I am talking about). There's a lotta things about MyService you don't know anything about. Things you wouldn't understand. Things you couldn't. . . let me state this plainly. No services depend on MyService and MyService depends on no other services. Addendum MyOtherService and SonOfMyService both seem to behave correctly at this point in the code. All of these services share the same characteristics (they're our own services we hatched in a secret lab and have no dependencies). Is it possible there is something wrong with the MyService install or something? I do know that if I stop debugging at this point, MyService is still listed as running in Services (even after hitting refresh). If I try to restart it then (or run my application again and get to this point), I get a message about it not being able to accept control messages. After that, the service shows up as stopped and I can start it normally. Why isn't the service being stopped? Is this a quirk of win 7? A failing on my part to understand the ServiceController, or Win Services in general?

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  • wget not behaving via IPC::Open3 vs bash

    - by Ryley
    I'm trying to stream a file from a remote website to a local command and am running into some problems when trying to detect errors. The code looks something like this: use IPC::Open3; my @cmd = ('wget','-O','-','http://10.10.1.72/index.php');#any website will do here my ($wget_pid,$wget_in,$wget_out,$wget_err); if (!($wget_pid = open3($wget_in,$wget_out,$wget_err,@cmd))){ print STDERR "failed to run open3\n"; exit(1) } close($wget_in); my @wget_outs = <$wget_out>; my @wget_errs = <$wget_err>; print STDERR "wget stderr: ".join('',@wget_errs); #page and errors outputted on the next line, seems wrong print STDERR "wget stdout: ".join('',@wget_outs); #clean up after this, not shown is running the filtering command, closing and waitpid'ing When I run that wget command directly from the command-line and redirect stderr to a file, something sane happens - the stdout will be the downloaded page, the stderr will contain the info about opening the given page. wget -O - http://10.10.1.72/index.php 2> stderr_test_file When I run wget via open3, I'm getting both the page and the info mixed together in stdout. What I expect is the loaded page in one stream and STDERR from wget in another. I can see I've simplified the code to the point where it's not clear why I want to use open3, but the general plan is that I wanted to stream stdout to another filtering program as I received it, and then at the end I was going to read the stderr from both wget and the filtering program to determine what, if anything went wrong. Other important things: I was trying to avoid writing the wget'd data to a file, then filtering that file to another file, then reading the output. It's key that I be able to see what went wrong, not just reading $? 8 (i.e. I have to tell the user, hey, that IP address is wrong, or isn't the right kind of website, or whatever). Finally, I'm choosing system/open3/exec over other perl-isms (i.e. backticks) because some of the input is provided by untrustworthy users.

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  • How to stream XML data using XOM?

    - by Jonik
    Say I want to output a huge set of search results, as XML, into a PrintWriter or an OutputStream, using XOM. The resulting XML would look like this: <?xml version="1.0" encoding="UTF-8"?> <resultset> <result> [child elements and data] </result> ... ... [1000s of result elements more] </resultset> Because the resulting XML document could be big (tens or hundreds of megabytes, perhaps), I want to output it in a streaming fashion (instead of creating the whole Document in memory and then writing that). The granularity of outputting one <result> at a time is fine, so I want to generate one <result> after another, and write it into the stream. Assume there's already a method that helps with iterating the results and generating Element objects: public nu.xom.Element getNextResult(); So I'd simply like to do something like this pseudocode (automatic flushing enabled, so don't worry about that) : open stream/writer write declaration write start tag for <resultset> while more results: write next <result> element write end tag for <resultset> close stream/writer I've been looking at Serializer, but the necessary methods, writeStartTag(Element), writeEndTag(Element), write(DocType) are protected, not public! Is there no other way than to subclass Serializer to be able to use those methods, or to manually write the start and end tags directly into the stream as Strings, bypassing XOM altogether? (The latter wouldn't be too bad in this simple example, but in the general case it would get quite ugly.) Am I missing something or is XOM just not made for this? With dom4j I could do this easily using XMLWriter - it has constructors that take a Writer or OutputStream, and methods writeOpen(Element), writeClose(Element), writeDocType(DocumentType) etc. Compare to XOM's Serializer where the only public write method is the one that takes a whole Document. Please refrain from answering if you're not familiar with XOM! I specifically want to know if and how you can do this kind of streaming with that library. (This is related to my question about the best dom4j replacement where XOM is a strong contender.)

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  • Various GPS Android Functionality Questions..

    - by Tyler
    Hello - I have a few questions (so far) with the the LocationManager on Android and GPS in general.. Feel free to answer any number of the questions below, and I appreciate your help in advance! (I noticed this stuff doesn't appear to be documented very well, so hopefully these questions will help others out too!) 1) I am using the following code, but I think there may be extra fluff in here that I do not need. Can you tell me if I can delete any of this? LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE); LocationListener locationListener = new MyLocationListener(); lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener); LocationProvider locationProvider = lm.getProvider("gps"); Location currentLocation = lm.getLastKnownLocation(locationProvider.getName()); 2) Is there a way to hold off on the last step (accessing "getLastKnownLocation" until after I am sure I have a GPS lock? What happens if this is called and GPS is still looking for signal? 3) MOST importantly, I want to ensure I have a GPS lock before I proceed to my next method, so is there a way to check to see if GPS is locked on and getLastKnownLocation is up to date? 4) Is there a way to 'shut down' the GPS listener once it does receive a lock and getLastKnownLocation is updated? I don't see a need to keep this running for my application once I have obtained a lock.. 5) Can you please confirm my assumption that "getLastKnownLocation" is updated frequently as the receiver moves? 6) In my code, I also have a class called "MyLocationListener" (code below) that I honestly just took from another example.. Is this actually needed? I assume this updates my location manager whenever the location changes, but it sure doesn't appear that there is much to the class itself! private class MyLocationListener implements LocationListener { @Override public void onLocationChanged(Location loc) { if (loc != null) { //Toast.makeText(getBaseContext(), "Location changed : Lat: " + loc.getLatitude() + " Lng: " + loc.getLongitude(), Toast.LENGTH_SHORT).show(); } } @Override public void onProviderDisabled(String provider) { // TODO Auto-generated method stub } @Override public void onProviderEnabled(String provider) { // TODO Auto-generated method stub } @Override public void onStatusChanged(String provider, int status, Bundle extras) { // TODO Auto-generated method stub } }

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  • Noob LINQ - reading, filtering XML with XDocument

    - by user316117
    I'm just learning XDocument and LINQ queries. Here's some simple XML (which doesn't look formatted exactly right in this forum in my browser, but you get the idea . . .) <?xml version="1.0" encoding="utf-8"?> <quiz xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.example.com/name XMLFile2.xsd" title="MyQuiz1"> <q_a> <q_a_num>1</q_a_num> <q_>Here is question 1</q_> <_a>Here is the answer to 1</_a> </q_a> <q_a> <q_a_num>2</q_a_num> <q_>Here is question 2</q_> <_a>Here is the answer to 2</_a> </q_a> </quiz> I can iterate across all elements in my XML file and display their Name, Value, and NodeType in a ListBox like this, no problem: XDocument doc = XDocument.Load(sPath); IEnumerable<XElement> elems = doc.Descendants(); IEnumerable<XElement> elem_list = from elem in elems select elem; foreach (XElement element in elem_list) { String str0 = "Name = " + element.Name.ToString() + ", Value = " + element.Value.ToString() + ", Nodetype = " + element.NodeType.ToString(); System.Windows.Controls.Label strLabel = new System.Windows.Controls.Label(); strLabel.Content = str0; listBox1.Items.Add(strLabel); } ...but now I want to add a "where" clause to my query so that I only select elements with a certain name (e.g., "qa") but my element list comes up empty. I tried . . . IEnumerable<XElement> elem_list = from elem in elems where elem.Name.ToString() == "qa" select elem; Could someone please explain what I'm doing wrong? (and in general are there some good tips for debugging Queries?) Thanks in advance!

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  • Is it possible to reliably auto-decode user files to Unicode? [C#]

    - by NVRAM
    I have a web application that allows users to upload their content for processing. The processing engine expects UTF8 (and I'm composing XML from multiple users' files), so I need to ensure that I can properly decode the uploaded files. Since I'd be surprised if any of my users knew their files even were encoded, I have very little hope they'd be able to correctly specify the encoding (decoder) to use. And so, my application is left with task of detecting before decoding. This seems like such a universal problem, I'm surprised not to find either a framework capability or general recipe for the solution. Can it be I'm not searching with meaningful search terms? I've implemented BOM-aware detection (http://en.wikipedia.org/wiki/Byte_order_mark) but I'm not sure how often files will be uploaded w/o a BOM to indicate encoding, and this isn't useful for most non-UTF files. My questions boil down to: Is BOM-aware detection sufficient for the vast majority of files? In the case where BOM-detection fails, is it possible to try different decoders and determine if they are "valid"? (My attempts indicate the answer is "no.") Under what circumstances will a "valid" file fail with the C# encoder/decoder framework? Is there a repository anywhere that has a multitude of files with various encodings to use for testing? While I'm specifically asking about C#/.NET, I'd like to know the answer for Java, Python and other languages for the next time I have to do this. So far I've found: A "valid" UTF-16 file with Ctrl-S characters has caused encoding to UTF-8 to throw an exception (Illegal character?) (That was an XML encoding exception.) Decoding a valid UTF-16 file with UTF-8 succeeds but gives text with null characters. Huh? Currently, I only expect UTF-8, UTF-16 and probably ISO-8859-1 files, but I want the solution to be extensible if possible. My existing set of input files isn't nearly broad enough to uncover all the problems that will occur with live files. Although the files I'm trying to decode are "text" I think they are often created w/methods that leave garbage characters in the files. Hence "valid" files may not be "pure". Oh joy. Thanks.

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  • C++: compute a number's complement and its number of possible mismatches

    - by Eagle
    I got a bit stuck with my algorithm and I need some help to solve my problem. I think an example would explain better my problem. Assuming: d = 4 (maximum number of allowed bits in a number, 2^4-1=15). m_max = 1 (maximum number of allowed bits mismatches). kappa = (maximum number of elements to find for a given d and m, where m in m_max) The main idea is for a given number, x, to compute its complement number (in binary base) and all the possible combinations for up to m_max mismatches from x complement's number. Now the program start to scan from i = 0 till 15. for i = 0 and m = 0, kappa = \binom{d}{0} = 1 (this called a perfect match) possible combinations in bits, is only 1111 (for 0: 0000). for i = 0 and m = 1, kappa = \binom{d}{1} = 4 (one mismatch) possible combinations in bits are: 1000, 0100, 0010 and 0001 My problem was to generalize it to general d and m. I wrote the following code: #include <stdlib.h> #include <iomanip> #include <boost/math/special_functions/binomial.hpp> #include <iostream> #include <stdint.h> #include <vector> namespace vec { typedef std::vector<unsigned int> uint_1d_vec_t; } int main( int argc, char* argv[] ) { int counter, d, m; unsigned num_combination, bits_mask, bit_mask, max_num_mismatch; uint_1d_vec_t kappa; d = 4; m = 2; bits_mask = 2^num_bits - 1; for ( unsigned i = 0 ; i < num_elemets ; i++ ) { counter = 0; for ( unsigned m = 0 ; m < max_num_mismatch ; m++ ) { // maximum number of allowed combinations num_combination = boost::math::binomial_coefficient<double>( static_cast<unsigned>( d ), static_cast<unsigned>(m) ); kappa.push_back( num_combination ); for ( unsigned j = 0 ; j < kappa.at(m) ; j++ ) { if ( m == 0 ) v[i][counter++] = i^bits_mask; // M_0 else { bit_mask = 1 << ( num_bits - j ); v[i][counter++] = v[i][0] ^ bits_mask } } } } return 0; } I got stuck in the line v[i][counter++] = v[i][0] ^ bits_mask since I was unable to generalize my algorithm to m_max1, since I needed for m_max mismatches m_max loops and in my original problem, m is unknown until runtime.

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  • Optimizing jQuery for Tabs

    - by jpdbaugh
    I am in the process of developing a widget. The widget has three tabs that are implemented in the following way. <div id="widget"> <ul id="tabs"> <li><a href="http...">One</a></li> <li><a href="http...">Two</a></li> <li><a href="http...">Three</a></li> </ul> <div id="tab_container"> <div id="tab_content"> //Tab Content goes here... </div> </div> </div> // The active class is initialized when the document loads $("#tabs li a").click(function() { $("#tabs li.active").removeClass("active"); $("#tab_content").load($(this).attr('href')); $(this).parent().addClass("active"); return false; }); The problem I am having is that the jquery code that have written is very slow. If the user changes tabs quickly the widget gets behing and bogged down. This causes the tabs to to not align with the data being displayed and just general lag. I believe that this is because the tab is being changed before $.load() is finished. I have tried to implement the following: ("#tabs li a").click(function() { $("#tabs li.active").removeClass("active"); $("#tab_content").load($(this).attr('href'), function (){ $(this).parent().addClass("active"); }); return false; }); It is my understanding that the callback function within in the load function does not execute until the load function is completed. I think this would solve my problem, however I can not come up with a way to select the correct tab that was clicked within the callback function. If this is not the way to do this then what is the best way implement these tabs so that they would stop loading an old request and load the newest tab selection by the user? Thanks

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  • Zaypay alternatives for payments using call or sms

    - by JohannesH
    We are currently trying to implement a payment provider in zaypay for paying for services using sms or by calling a number. We already have google checkout and paypal working for regular payments but zaypay is rather inflexible, poorly documented and a pain to setup when you have hundreds of products with varying prices. So my question is, do you know of any other european payment providers that take sms and call payments? As a response to Roberts answer/question Hi Robert, I must say that the Zaypay solution is the best and only I've seen thus far regarding phoned payments. However, since its now 2 months ago I finished the implementation of our custom Zaypay UI I can't remember much of the the details of the problems we were having. I'll try to give a brief of them anyways the best I can. First of all I would like to see a redirection type scenario for payalogues. From what I remember you guys are using the JS framework "Prototype" which doesn't play nice with jQuery which we are using so we weren't able to use the popup-type scenario supported by payalogues. Furthermore when implementing our custom interface I remember a lot of missing translations, like words that were codes instead of a word or a phrase. This meant we ended up writing/translating all the messages we needed ourselves. Also, another point of annoyance was the setup of prices and items. I wish we could just send in the order items/prices as a part of the interface like you can in Google Checkout or PayPal (not that they're flawless either), instead of having to define ALL the items you will ever sell through your admin interface beforehand. As far as I can remember it is virtually impossible to use Zaypay for a multi-item order in its current form. Finally there are, as far as I can tell, some security issues that you have to think about when you implement a custom solution... especially a ajax driven one. As I said in my original post you do mention this in the documentation but I believe the documentation wasn't that comprehensive regarding security issues. Again I wish I could give more details but the code & client is long since gone, so I can't look up the comments I wrote. Sorry! Oh yeah, the general API documentation weren't exactly comprehensive and 100% correct either. Again, I don't want to advice people against using Zaypay, I just want to advice that they should try it out first on a realistic prototype and think about their implementation before releasing to production. Maybe its just me who misunderstood a lot of things but I generally had a difficult time using your framework and I was left with a feeling that the API was very new and not thought through from the beginning.

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  • Available Coroutine Libraries in Java

    - by JUST MY correct OPINION
    I would like to do some stuff in Java that would be clearer if written using concurrent routines, but for which full-on threads are serious overkill. The answer, of course, is the use of coroutines, but there doesn't appear to be any coroutine support in the standard Java libraries and a quick Google on it brings up tantalising hints here or there, but nothing substantial. Here's what I've found so far: JSIM has a coroutine class, but it looks pretty heavyweight and conflates, seemingly, with threads at points. The point of this is to reduce the complexity of full-on threading, not to add to it. Further I'm not sure that the class can be extracted from the library and used independently. Xalan has a coroutine set class that does coroutine-like stuff, but again it's dubious if this can be meaningfully extracted from the overall library. It also looks like it's implemented as a tightly-controlled form of thread pool, not as actual coroutines. There's a Google Code project which looks like what I'm after, but if anything it looks more heavyweight than using threads would be. I'm basically nervous of something that requires software to dynamically change the JVM bytecode at runtime to do its work. This looks like overkill and like something that will cause more problems than coroutines would solve. Further it looks like it doesn't implement the whole coroutine concept. By my glance-over it gives a yield feature that just returns to the invoker. Proper coroutines allow yields to transfer control to any known coroutine directly. Basically this library, heavyweight and scary as it is, only gives you support for iterators, not fully-general coroutines. The promisingly-named Coroutine for Java fails because it's a platform-specific (obviously using JNI) solution. And that's about all I've found. I know about the native JVM support for coroutines in the Da Vinci Machine and I also know about the JNI continuations trick for doing this. These are not really good solutions for me, however, as I would not necessarily have control over which VM or platform my code would run on. (Indeed any bytecode manipulation system would suffer similar problems -- it would be best were this pure Java if possible. Runtime bytecode manipulation would restrict me from using this on Android, for example.) So does anybody have any pointers? Is this even possible? If not, will it be possible in Java 7? Edited to add: Just to ensure that confusion is contained, this is a related question to my other one, but not the same. This one is looking for an existing implementation in a bid to avoid reinventing the wheel unnecessarily. The other one is a question relating to how one would go about implementing coroutines in Java should this question prove unanswerable. The intent is to keep different questions on different threads.

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  • How to combine designable components with dependency injection

    - by Wim Coenen
    When creating a designable .NET component, you are required to provide a default constructor. From the IComponent documentation: To be a component, a class must implement the IComponent interface and provide a basic constructor that requires no parameters or a single parameter of type IContainer. This makes it impossible to do dependency injection via constructor arguments. (Extra constructors could be provided, but the designer would ignore them.) Some alternatives we're considering: Service Locator Don't use dependency injection, instead use the service locator pattern to acquire dependencies. This seems to be what IComponent.Site.GetService is for. I guess we could create a reusable ISite implementation (ConfigurableServiceLocator?) which can be configured with the necessary dependencies. But how does this work in a designer context? Dependency Injection via properties Inject dependencies via properties. Provide default instances if they are necessary to show the component in a designer. Document which properties need to be injected. Inject dependencies with an Initialize method This is much like injection via properties but it keeps the list of dependencies that need to be injected in one place. This way the list of required dependencies is documented implicitly, and the compiler will assists you with errors when the list changes. Any idea what the best practice is here? How do you do it? edit: I have removed "(e.g. a WinForms UserControl)" since I intended the question to be about components in general. Components are all about inversion of control (see section 8.3.1 of the UMLv2 specification) so I don't think that "you shouldn't inject any services" is a good answer. edit 2: It took some playing with WPF and the MVVM pattern to finally "get" Mark's answer. I see now that visual controls are indeed a special case. As for using non-visual components on designer surfaces, I think the .NET component model is fundamentally incompatible with dependency injection. It appears to be designed around the service locator pattern instead. Maybe this will start to change with the infrastructure that was added in .NET 4.0 in the System.ComponentModel.Composition namespace.

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  • How do we, as a community, help encourage programming in public schools? (Or state Schools for the U

    - by NoMoreZealots
    PRIMARY MOTIVATION My office gets involved with the "First Robotics" competitions and one thing that lingers year to year is the students typically have no preparation for doing even simple programming as part of the public schools system. While the science classes provide some basic grasp of mechanical and electrical concepts, by in large computer programming gets no coverage from the curriculum. (This my be different in other areas of the country/world.) What makes it worse is there is only a short period of time you have to prepare the student's and help them design the robot. Talking to some professors from local colleges, it's a problem because you can't assume even the most basic understanding for freshman CS majors. Languages like Python, Lua and BASIC are simple enough for at least high school level students, if not younger. SCOPE So how do you get public schools to support a programming, at least to the level of "Try it in BASIC" examples that used to be at the end of a chapter in my Algebra book? At least enough to prepare them for event's such as the FIRST Robotic competitions. Which the primary objectives are to teach problem solving and team work, and to possible foster an interest in Math, Science and Engineering in general. (Not force feed to them, as some people her seem to be implying.) Edit: Why teach kids: (Since 2000 CS enrollment in US colleges has decreased by 70% while college enrollment has increased, this is a PROBLEM.) Saying there is no value in teaching someone programming in Jr./High school because they might think "they know programming." Is like saying there's no value in teaching High school science and physics, because they might decide they "know physics." Leading to abuse like: "I passed a high school physics class, I'm going to develop a Unified Quantum Gravitational Theory." Better Prepared students are better students. Instead it would allows college programs to raise the bar on the entry level courses, allowing students to be weeded out based on their understanding of more advanced material. Plus people who did poorly in that in topic in High school aren't as likely to say "I think there's money in computer's so I'll computer science." Plus if people take it in high school and decide THEN that it's not for them, it's better than them wasting their money to PAY a college to figure that out. The result is that people who take the degree are more likely to succeed and be there for the RIGHT reasons. (i.e. It's what they REALLY want to do. And that's REALLY the key to being good at anything.) Programming is like anything else, the more practice and genuine interest you have the better you get. If you start them later, they get less practice. The earlier give them the opportunity to start, the more practice they will get. All other things equal, the more practice the better the programmer.

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  • Managing multiple AJAX calls to PHP scripts

    - by relativelycoded
    I have a set of 5 HTML dropdowns that act as filters for narrowing results returned from a mySQL database. The three pertinent filters are for "Province", "Region", and "City" selection, respectively. I have three functions: findSchools(), which runs when any of the filters (marked with CSS class .filter) are changed, and fetches the results via AJAX from a PHP script. Once that is done, two other functions are called... changeRegionOptions(), which, upon changing the "Province" filter, and updates the available options using the same method as the first function, but posting to a different script. changeCityOptions(), which runs if the "Region" filter was changed, and updates options, again using the same method. The problem is that since I want these AJAX functions to run simultaneously, and they by nature run asynchronously, I've tried using $.when to control the execution of the functions, but it doesn't fix the problem. The functions run, but the Region and City filters return blank (no options); the FireBug report shows absolutely no output, even though the POST request went through. The posted parameter for filter_province gets sent normally, but the one for region gets cut off at the end -- it sends as filter_region=, with no value passed. So I'm presuming my logic is wrong somewhere. The code is below: // When any of the filters are changed, let's query the database... $("select.filter").change(function() { findSchools(); }); // First, we see if there are any results... function findSchools() { var sch_province = document.filterform.filter_province.value; var sch_region = document.filterform.filter_region.value; var sch_city = document.filterform.filter_city.value; var sch_cat = document.filterform.filter_category.value; var sch_type = document.filterform.filter_type.value; $.post("fetch_results.php", { filter_province : sch_province, filter_region : sch_region, filter_city : sch_city, filter_category : sch_cat, filter_type : sch_type }, function(data) { $("#results").html(""); $("#results").hide(); $("#results").html(data); $("#results").fadeIn(600); } ); // Once the results are fetched, we want to see if the filter they changed was the one for Province, and if so, update the Region and City options to match that selection... $("#filter_province").change(function() { $.when(findSchools()) .done(changeRegionOptions()); $.when(changeRegionOptions()) .done(changeCityOptions()); }); }; This is just one of the ways I've tried to solve it; I've tried using an IF statement, and tried calling the functions directly inside the general select.filter.change() function (after findSchools(); ), but they all return the same result. Any help with this would be great!

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  • ArithmeticException thrown during BigDecimal.divide

    - by polygenelubricants
    I thought java.math.BigDecimal is supposed to be The Answer™ to the need of performing infinite precision arithmetic with decimal numbers. Consider the following snippet: import java.math.BigDecimal; //... final BigDecimal one = BigDecimal.ONE; final BigDecimal three = BigDecimal.valueOf(3); final BigDecimal third = one.divide(three); assert third.multiply(three).equals(one); // this should pass, right? I expect the assert to pass, but in fact the execution doesn't even get there: one.divide(three) causes ArithmeticException to be thrown! Exception in thread "main" java.lang.ArithmeticException: Non-terminating decimal expansion; no exact representable decimal result. at java.math.BigDecimal.divide It turns out that this behavior is explicitly documented in the API: In the case of divide, the exact quotient could have an infinitely long decimal expansion; for example, 1 divided by 3. If the quotient has a non-terminating decimal expansion and the operation is specified to return an exact result, an ArithmeticException is thrown. Otherwise, the exact result of the division is returned, as done for other operations. Browsing around the API further, one finds that in fact there are various overloads of divide that performs inexact division, i.e.: final BigDecimal third = one.divide(three, 33, RoundingMode.DOWN); System.out.println(three.multiply(third)); // prints "0.999999999999999999999999999999999" Of course, the obvious question now is "What's the point???". I thought BigDecimal is the solution when we need exact arithmetic, e.g. for financial calculations. If we can't even divide exactly, then how useful can this be? Does it actually serve a general purpose, or is it only useful in a very niche application where you fortunately just don't need to divide at all? If this is not the right answer, what CAN we use for exact division in financial calculation? (I mean, I don't have a finance major, but they still use division, right???).

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  • Move options between multiple dropdown lists

    - by Martha
    We currently have a form with the standard multi-select functionality of "here are the available options, here are the selected options, here are some buttons to move stuff back and forth." However, the client now wants the ability to not just select certain items, but to also categorize them. For example, given a list of books, they want to not just select the ones they own, but also the ones they've read, the ones they would like to read, and the ones they've heard about. (All examples fictional.) Thankfully, a selected item can only be in one category at a time. I can find many examples of moving items between listboxes, but not a single one for moving items between multiple listboxes. To add to the complication, the form needs to have two sets of list+categories, e.g. a list of movies that need to be categorized in addition to the aforementioned books. An additional problem is that sorting between lists is all well and good in the javascript-enabled world, but I can't really think of a good fallback interface for, say, mobile browsers. Maybe a pseudo-listbox with radio buttons next to each item? The master list of items will in general be very long - over 100 items, certainly, possibly many more. Any given category will most likely contain one or two selected items, but the possibility exists for a category to have dozens of selected items, or zero selected items. As far as OS and stuff, the site is in classic asp (quit snickering!), the server-side code is VBScript, and so far we've avoided the various Javascript libraries by the simple expedient of almost never using client-side scripting. This one form for this one client is currently the big exception. Give 'em an inch and they want a mile... Oh, and I have to add: I suck at Javascript, or really at any C-descendant language. Curly braces give me hives. I'd really, really like something I can just copy & paste into my page, maybe tweak some variable names, and never look at it again. A girl can dream, can't she? :)

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  • Adding NavigationControl to a TabBar Application containing UITableViews

    - by kungfuslippers
    Hi, I'm new to iPhone dev and wanted to get advice on the general design pattern / guide for putting a certain kind of app together. I'm trying to build a TabBar type application. One of the tabs needs to display a TableView and selecting a cell from within the table view will do something else - maybe show another table view or a web page. I need a Navigation Bar to be able to take me back from the table view/web page. The approach I've taken so far is to: Create an app based around UITabBarController as the rootcontroller i.e. @interface MyAppDelegate : NSObject <UIApplicationDelegate> { IBOutlet UIWindow *window; IBOutlet UITabBarController *rootController; } Create a load of UIViewController derived classes and associated NIBs and wire everything up in IB so when I run the app I get the basic tabs working. I then take the UIViewController derived class and modify it to the following: @interface MyViewController : UIViewController<UITableViewDataSource, UITableViewDelegate> { } and I add the delegate methods to the implementation of MyViewController - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return 2; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } if (indexPath.row == 0) { cell.textLabel.text = @"Mummy"; } else { cell.textLabel.text = @"Daddy"; } return cell; } Go back to IB , open MyViewController.xib and drop a UITableView onto it. Set the Files Owner to be MyViewController and then set the delegate and datasource of the UITableView to be MyViewController. If I run the app now, I get the table view appearing with mummy and daddy working nicely. So far so good. The question is how do I go about incorporating a Navigation Bar into my current code for when I implement: - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath() { // get row selected NSUInteger row = [indexPath row]; if (row == 0) { // Show another table } else if (row == 1) { // Show a web view } } Do I drop a NavigationBar UI control onto MyControllerView.xib ? Should I create it programmatically? Should I be using a UINavigationController somewhere ? I've tried dropping a NavigationBar onto my MyControllerView.xib in IB but its not shown when I run the app, only the TableView is displayed.

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  • Memory efficient int-int dict in Python

    - by Bolo
    Hi, I need a memory efficient int-int dict in Python that would support the following operations in O(log n) time: d[k] = v # replace if present v = d[k] # None or a negative number if not present I need to hold ~250M pairs, so it really has to be tight. Do you happen to know a suitable implementation (Python 2.7)? EDIT Removed impossible requirement and other nonsense. Thanks, Craig and Kylotan! To rephrase. Here's a trivial int-int dictionary with 1M pairs: >>> import random, sys >>> from guppy import hpy >>> h = hpy() >>> h.setrelheap() >>> d = {} >>> for _ in xrange(1000000): ... d[random.randint(0, sys.maxint)] = random.randint(0, sys.maxint) ... >>> h.heap() Partition of a set of 1999530 objects. Total size = 49161112 bytes. Index Count % Size % Cumulative % Kind (class / dict of class) 0 1 0 25165960 51 25165960 51 dict (no owner) 1 1999521 100 23994252 49 49160212 100 int On average, a pair of integers uses 49 bytes. Here's an array of 2M integers: >>> import array, random, sys >>> from guppy import hpy >>> h = hpy() >>> h.setrelheap() >>> a = array.array('i') >>> for _ in xrange(2000000): ... a.append(random.randint(0, sys.maxint)) ... >>> h.heap() Partition of a set of 14 objects. Total size = 8001108 bytes. Index Count % Size % Cumulative % Kind (class / dict of class) 0 1 7 8000028 100 8000028 100 array.array On average, a pair of integers uses 8 bytes. I accept that 8 bytes/pair in a dictionary is rather hard to achieve in general. Rephrased question: is there a memory-efficient implementation of int-int dictionary that uses considerably less than 49 bytes/pair?

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  • Strange behaviour of NSString in NSView

    - by Mee
    Trying to create a Skat-Game, I encountered the following problem: isBidding is a Boolean value indicationg, the program is in a certain state, [desk selected] is a method calling returning the current selected player, chatStrings consists of dictionaries, saving strings with the player, who typed, and what he typed - (void)drawRect:(NSRect)rect { NSMutableDictionary * attributes = [NSMutableDictionary dictionary]; [attributes setObject:[NSFont fontWithName:playerFont size:playerFontSize] forKey:NSFontAttributeName]; [attributes setObject:playerFontColor forKey:NSForegroundColorAttributeName]; [[NSString stringWithFormat:@"Player %i",[desk selected] + 1]drawInRect:playerStringRect withAttributes:attributes]; if (isBidding) { [attributes setObject:[NSFont fontWithName:chatFont size:chatFontSize] forKey:NSFontAttributeName]; [attributes setObject:chatFontColor forKey:NSForegroundColorAttributeName]; int i; for (i = 0; i < [chatStrings count]; i++, yProgress -= 20) { if (isBidding) [[NSString stringWithFormat:@"Player %i bids: %@",[[[chatStrings objectAtIndex:i]valueForKey:@"Player"]intValue], [[chatStrings objectAtIndex:i]valueForKey:@"String"]] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; else [[NSString stringWithFormat:@"Player %i: %@",[[[chatStrings objectAtIndex:i]valueForKey:@"Player"]intValue], [[chatStrings objectAtIndex:i]valueForKey:@"String"]] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; } if (isBidding) [[NSString stringWithFormat:@"Player %i bids: %@",[desk selected] + 1, displayString] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; else [[NSString stringWithFormat:@"Player %i: %@",[desk selected] + 1, displayString] drawAtPoint:NSMakePoint([self bounds].origin.x, yProgress) withAttributes:attributes]; yProgress = chatFontBegin; } } This is the part determining the string's content, the string is contributed by an [event characters] method. -(void)displayChatString:(NSString *)string { displayString = [displayString stringByAppendingString:string]; [self setNeedsDisplay:YES]; } The problem if have is this: when typing in more than two letters the view displays NSRectSet{{{471, 574},{500, 192}}} and returns no more discription when I try to print it. then I get an EXC_BAD_ACCESS message, though I have not released it (as far as I can see) I also created the string with alloc and init, so I cannot be in the autorelease pool. I also tried to watch the process when it changes with the debugger, but I couldn't find any responsible code. As you can see I am still a beginner in Cocoa (and programming in general), so I would be really happy if somebody would help me with this.

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  • Closure Tables - Is this enough data to display a tree view?

    - by James Pitt
    Here is the table I have created by testing the closure table method. | id | parentId | childId | hops | | | | | 270 | 6 | 6 | 0 | 271 | 7 | 7 | 0 | 272 | 8 | 8 | 0 | 273 | 9 | 9 | 0 | 276 | 10 | 10 | 0 | 281 | 9 | 10 | 1 | 282 | 7 | 9 | 1 | 283 | 7 | 10 | 2 | 285 | 7 | 8 | 1 | 286 | 6 | 7 | 1 | 287 | 6 | 9 | 2 | 288 | 6 | 10 | 3 | 289 | 6 | 8 | 2 | 293 | 6 | 9 | 1 | 294 | 6 | 10 | 2 I am trying to create a simple tree of this using PHP. There does not seem to be enough data to create the table. For example, when I look purely at parentId = 6: -Part 6 -Part 7 - ? - ? -Part 9 - ? - ? We know that parts 8 and 10 exists below Part 7 or 9, but not which. We know that part 10 exists at both 3 and 4 nodes deep but where? If I look at other data in the table it is possible to tell it should be: - Part 6 - Part 7 - Part 9 - Part 10 - Part 9 - Part 10 I thought one of the benefits of closure tables was there was no need for recursive queries? Could you help explain what I am doing wrong? EDIT: For clarification, this is a mapping table. There is another table called "parts" which has a column called part_id that correlates to both the parentId and childId columns in the "closure" table. The "id" column in the table above (closure) is just for the purposes of maintaining a primary key. It is not really necessary. The methods I have used to create this closure table is described in the following article: http://dirtsimple.org/2010/11/simplest-way-to-do-tree-based-queries.html EDIT2: It can have two and three hops. I will explain easier by assigning names to the items. Part 6 = Bicycle Part 7 = Gears Part 8 = Chain Part 9 = Bolt Part 10 = Nut Nut is part of Bolt. The Bolt and Nut combo exists directly within Bicycle and within Gears which is part of Bicycle. In relation to what method to use I have looked at Adjacency, Edges, Enum Paths, Closures, DAGS(networks) and the Nested Set Model. I am still trying to work out what is what, but this is an extremely complex component database where there are multiple parents and any modification to a sub-tree must propogate through the other trees. More importantly there will be insertions, deletions and tree views that I wish to avoid recursion during general use, even at the cost of database space and query time during entry.

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  • jQuery 1.4.2 and IE6: change event not firing first time using keyboard

    - by macca1
    I've done a good amount of research on this and found a bunch of reported problems and solutions but the general consensus seems that all change problems in IE6 were fixed in jQuery 1.4.2. I'm having an issue where a change event is not firing in jQuery 1.4.2, but it did fire successfully in jQuery 1.3.2. This is in IE6. I'm about to submit a bug for this, but for my sanity I wanted to post it here first to see if there's something dumb I'm missing. I don't understand why this is working this way... <HTML> <HEAD> <TITLE>jQuery 1.4.2 Problem </TITLE> <script src="jquery-1.4.2.min.js" type="text/javascript"></script> <script> $(document).ready( function() { $("#firstBox").change(function() { alert("CHANGE"); }); // ONLOAD of document autofocus into the first element... $("form").find(":input:visible:first").focus() }); </script> </HEAD> <BODY> <form> <select id="firstBox"> <option value="" selected="selected">--</option> <option value="1">One</option> <option value="2">Two</option> </select> <br><br> <input size="10" id="secondBox"> </form> </BODY> </HTML> Simple enough, right? Onload of the page, give the first element focus. Onchange of the first element, alert. If you use the mouse, it works as expected. The page loads, the focus is in the drop down, you change the option, you get the alert. The problem is if you use the keyboard. The page loads, the focus is in the drop down, you press the down arrow. The option changes. Tab off the field, no alert. Weird. To make it even weirder, if you tab back into the field and change it again (all using the keyboard), the change event DOES fire after tab out this time. Any ideas?

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