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  • python networkx

    - by krisdigitx
    hi, i am trying to use networkx with python, when i run this program, it get this error, is there anything missing? #!/usr/bin/env python import networkx as nx import matplotlib import matplotlib.pyplot import matplotlib.pyplot as plt G=nx.Graph() G.add_node(1) G.add_nodes_from([2,3,4,5,6,7,8,9,10]) #nx.draw_graphviz(G) #nx_write_dot(G, 'node.png') nx.draw(G) plt.savefig("/var/www/node.png") Traceback (most recent call last): File "graph.py", line 13, in <module> nx.draw(G) File "/usr/lib/pymodules/python2.5/networkx/drawing/nx_pylab.py", line 124, in draw cf=pylab.gcf() File "/usr/lib/pymodules/python2.5/matplotlib/pyplot.py", line 276, in gcf return figure() File "/usr/lib/pymodules/python2.5/matplotlib/pyplot.py", line 254, in figure **kwargs) File "/usr/lib/pymodules/python2.5/matplotlib/backends/backend_tkagg.py", line 90, in new_figure_manager window = Tk.Tk() File "/usr/lib/python2.5/lib-tk/Tkinter.py", line 1650, in __init__ self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use) _tkinter.TclError: no display name and no $DISPLAY environment variable

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  • Ironpython call numpy problem

    - by Begtostudy
    Ironpython 2.6, python 2.6.5, numpy, SciPy import sys sys.path.append(r'D:\Python26\dll') sys.path.append(r'D:\Python26\Lib') sys.path.append(r'D:\Python26\Lib\site-packages') » import numpy Traceback (most recent call last): File "<string>", line 1, in <module> File "D:\Python26\Lib\site-packages\numpy\__init__.py", line 132, in <module> File "D:\Python26\Lib\site-packages\numpy\add_newdocs.py", line 9, in <module> File "D:\Python26\Lib\site-packages\numpy\lib\__init__.py", line 4, in <module> File "D:\Python26\Lib\site-packages\numpy\lib\type_check.py", line 8, in <module> File "D:\Python26\Lib\site-packages\numpy\core\__init__.py", line 5, in <module> ImportError: No module named multiarray What's wrong? Thanks.

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  • Publishing SWF using Adobe Flash

    - by Kim
    Hello everyone, I have a SWF file which contains of an image (1keyframe) and also, it contains an AS3 file with the following codes: var loader:Loader=new Loader(); var ur:URLRequest=new URLRequest("1.swf"); loader.load(ur); addChild(loader); so basically, i am trying to play the swf file (1.swf - an audio) while the image is being displayed. What I want to know is how will I be able to publish this project into an SWF file which can still play as expected even without the raw 1.swf file. I can publish SWF right now but when I delete the 1.swf file, my generated swf can only display the image. Help me please. Thanks in advance :)

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  • Perl Moose::Util::TypeConstraints bug ? what is this error about the name has invalid chars ?

    - by alex8657
    That has been hours i am tracking a Moose::Util::TypeConstraints exceptions, i don't understand where it gets to check a type and tells me that the name is incorrect. I tracked the error to a reduced example to try to locate the problem, and it just shows me that i do not get it. Did i get to a Moose::Util::TypeConstraints bug ? aoffice:new alex$ perl -c ../codesnippets/typeconstrainterror.pl ../codesnippets/typeconstrainterror.pl syntax OK aoffice:new alex$ perl -d ../codesnippets/typeconstrainterror.pl (...) DB<1> r Something::File::LocalFile=HASH(0x100d1bfa8) contains invalid characters for a type name. Names can contain alphanumeric character, ":", and "." at /opt/local/lib/perl5/vendor_perl/5.10.1/darwin-multi-2level/Moose/Util/TypeConstraints.pm line 508 Moose::Util::TypeConstraints::_create_type_constraint('Something::File::LocalFile=HASH(0x100d1bfa8)', undef, undef, undef, undef) called at /opt/local/lib/perl5/vendor_perl/5.10.1/darwin-multi-2level/Moose/Util/TypeConstraints.pm line 285 Moose::Util::TypeConstraints::type('Something::File::LocalFile=HASH(0x100d1bfa8)') called at ../codesnippets/typeconstrainterror.pl line 7 Something::File::is_slink('Something::File::LocalFile=HASH(0x100d1bfa8)') called at ../codesnippets/typeconstrainterror.pl line 33 Debugged program terminated. Use q to quit or R to restart, use o inhibit_exit to avoid stopping after program termination, h q, h R or h o to get additional info. Below, the code that crashes: package Something::File; use Moose; has 'type' =>(is=>'ro', isa=>'Str', writer=>'_set_type' ); sub is_slink { my $self = shift; return ( $self->type eq 'slink' ); } no Moose; __PACKAGE__->meta->make_immutable; 1; package Something::File::LocalFile; use Moose; use Moose::Util::TypeConstraints; extends 'Something::File'; subtype 'PositiveInt' => as 'Int' => where { $_ >0 } => message { 'Only positive greater than zero integers accepted' }; no Moose; __PACKAGE__->meta->make_immutable; 1; my $a = Something::File::LocalFile->new; # $a->_set_type('slink'); print $a->is_slink ." end\n";

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  • ungetc in Python

    - by Dragos Toader
    Some file read (readlines()) functions in Python copy the file contents to memory (as a list) I need to process a file that's too large to be copied in memory and as such need to use a file pointer (to access the file one byte at a time) -- as in C getc(). The additional requirement I have is that I'd like to rewind the file pointer to previous bytes like in C ungetc(). Is there a way to do this in Python? Also, in Python, I can read one line at a time with readline() Is there a way to read the previous line going backward?

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  • How to create SSIS package to update from one database to another database within same server

    - by Pavan Kumar
    My query is related to the answers i got for questions i had posted earlier in the same forum. I have a copy of a client database which is attached to SQL Server where the Central Database exists. The copy already contains the updated data. I just want to update from that copy to Central Database both holding same schema and are present in the same server using C# .NET. One of the solution i got was to create SSIS package and run it from the UI. I want to know as how i can create SSIS Package to achieve this. I am new to SSIS. I am using SQL Server 2005 Standard Edition and Visual Studio 2008 SP1 installed. I learnt that BIDS 2005 is used to create packages which comes by default with SQL Server 2005. Can someone please give me a example as i am new to this.

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  • How does Windows decide which icon format to display when showing an exe's icon in Windows Explorer?

    - by Malcolm
    How does Windows decide which icon format to display when showing an exe's icon in Windows Explorer? Problem: When we look at our icon file and exe with embedded icon file in various Windows Explorer file views, the icon file is displayed in a higher quality mode than the icon displayed for our executable even though the icon in our executable contains the exact same icon. Our exe's icon has jaggier edges which leads me to believe that Windows Explorer may be trying to upsize a lower resolution icon rather than picking an icon appropriate for the actual display size. In a multi-format icon file, is there a specific order we should use for positioning each icon format? For example, we have an icon file with icons in the following formats: - 16x16 - 32x32 - 48x48 - 64x64 - 128x128 - 256x256 We are testing the appearance of our exe's icon using Windows Explorer under Windows XP, Vista and Windows 7. Any suggestions appreciated.

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  • Java binary files writeUTF... explain specifications...

    - by user69514
    I'm studying Java on my own. One of the exercises is the following, however I do not really understand what it is asking to.... any smart java gurus out there that could explain this in more detail and simple words? Thanks Suppose that you have a binary file that contains numbers whos type is either int or double. You dont know the order of the numbers in the file, but their order is recorded in a string at the begining of the file. The string is composed of the letters i for int, and d for double, in the order of the types of the subsequent numbers. The string is written using the method writeUTF. For example the string "iddiiddd" indicated that the file contains eight values, as follows: one integer, followed by two doubles, followed by two integers, followed by three doubles. Read this binary file and create a new text file of the values written one to a line.

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  • Java: why is declaration not sufficient in interface?

    - by HH
    Big class contains Format-interfcase and Format-class. The Format-class contains the methods and the interface has the values of the fields. I could have the fields in the class Format but the goal is with Interface. So do I just create dummy-vars to get the errors away, design issue or something ELSE? KEY: Declaration VS Initialisation Explain by the terms, why you have to init in interface. What is the logic behind it? To which kind of problems it leads the use of interface? Sample Code having the init-interface-problem import java.util.*; import java.io.*; public class FormatBig { private static class Format implements Format { private static long getSize(File f){return f.length();} private static long getTime(File f){return f.lastModified();} private static boolean isFile(File f){if(f.isFile()){return true;}} private static boolean isBinary(File f){return Match.isBinary(f);} private static char getType(File f){return Match.getTypes(f);} private static String getPath(File f){return getNoErrPath(f);} //Java API: isHidden, --- SYSTEM DEPENDED: toURI, toURL Format(File f) { // PUZZLE 0: would Stack<Object> be easier? size=getSize(f); time=getTime(f); isfile=isFile(f); isBinary=isBinary(f); type=getType(f); path=getPath(f); //PUZZLE 1: how can simplify the assignment? values.push(size); values.push(time); values.push(isfile); values.push(isBinary); values.push(type); values.push(path); } } public static String getNoErrPath(File f) { try{return f.getCanonicalPath(); }catch(Exception e){e.printStackTrace();} } public static final interface Format { //ERR: IT REQUIRES "=" public long size; public long time; public boolean isFile=true; //ERROR goes away if I initialise wit DUMMY public boolean isBinary; public char type; public String path; Stack<Object> values=new Stack<Object>(); } public static void main(String[] args) { Format fm=new Format(new File(".")); for(Object o:values){System.out.println(o);} } }

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  • Emacs: annoying Flymake dialog box.

    - by baol
    Hello I have the following lines in my ~/.emacs.d/init.el (custom-set-variables '(flymake-allowed-file-name-masks (quote ( ("\\.cc\\'" flymake-simple-make-init) ("\\.cpp\\'" flymake-simple-make-init))))) (add-hook 'find-file-hook 'flymake-find-file-hook) When I open a cc/cpp file that has a Makefile with the following content in the same folder I get proper on-the-fly compilation and error reporting (Flymake will check the syntax and report errors and warnings during code editing) .PHONY: check-syntax check-syntax: $(CXX) -Wall -Wextra -pedantic -fsyntax-only $(CHK_SOURCES) The problem is that when I open a .cc file that has no corresponding Makefile i get an annoying dialog box that warns me about flymake being disabled for every file opened. Is there some hook I can use to disable that warning? Can you provide sample elisp code and explanation on how you found the proper hook?

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  • Facebook publish HTTP Error 400 : bad request

    - by Abhishek
    Hey I am trying to publish a score to Facebook through python's urllib2 library. import urllib2,urllib url = "https://graph.facebook.com/USER_ID/scores" data = {} data['score']=SCORE data['access_token']='APP_ACCESS_TOKEN' data_encode = urllib.urlencode(data) request = urllib2.Request(url, data_encode) response = urllib2.urlopen(request) responseAsString = response.read() I am getting this error: response = urllib2.urlopen(request) File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/urllib2.py", line 124, in urlopen return _opener.open(url, data, timeout) File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/urllib2.py", line 389, in open response = meth(req, response) File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/urllib2.py", line 502, in http_response 'http', request, response, code, msg, hdrs) File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/urllib2.py", line 427, in error return self._call_chain(*args) File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/urllib2.py", line 361, in _call_chain result = func(*args) File "/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/urllib2.py", line 510, in http_error_default raise HTTPError(req.get_full_url(), code, msg, hdrs, fp) urllib2.HTTPError: HTTP Error 400: Bad Request Not sure if this is relating to Facebook's Open Graph or improper urllib2 API use.

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  • Using XStream to deserialize an XML response with separate "success" and "failure" forms?

    - by Chris Markle
    I am planning on using XStream with Java to convert between objects and XML requests and XML responses and objects, where the XML is flowing over HTTP/HTTPS. On the response side, I can get a "successful" response, which seems like it would map to one Java class, or a "failure" response, which seems like it would map to another Java class. For example, for a "file list" request, I could get an affirmative response e.g., <?xml version="1.0" encoding="UTF-8"?> <response> <success>true</success> <files> <file>[...]</file> <file>[...]</file> <file>[...]</file> </files> </response> or I could get a negative response e.g., <?xml version="1.0" encoding="UTF-8"?> <response> <success>false</success> <error> <errorCode>-502</errorCode> <systemMessage>[...]AuthenticationException</systemMessage> <userMessage>Not authenticated</userMessage> </error> </response> To handle this, should I include fields in one class for both cases or should I somehow use XStream to "conditionally" create one of the two potential classes? The case with fields from both response cases in the same object would look something like this: Class Response { boolean success; ArrayList<File> files; ResponseError error; [...] } Class File { String name; long size; [...] } Class ResponseError { int errorCode; String systemMessage; String userMessage; [...] } I don't know what the "use XStream and create different objects in case of success or error" looks like. Is it possible to do that somehow? Is it better or worse way to go? Anyway, any advice on how to handle using XStream to deal with this success vs. failure response case would be appreciated. Thanks in advance!

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  • Batch build using IAR tools

    - by Jim Tshr
    I am trying to do a batch build of a project using IAR tools. The processor is a CC2530, and it builds fine in the IDE. I have followed the documentation for batch build (Project/Batch Build) and created a .cspy file that is suppose to be my batch file, but in the comments in that file it indicates that I need a debug file (.ubrof) to execute with it. I can't find a .ubrof file and I have searched the whole project directory structure. Also, I want my batch build to build a production version without the debugging information. Where do I get a .ubrof file? How do I do a production batch build using IAR tools?

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  • Android "gen" folder and SVN - bitter enemies.

    - by Benju
    It seems that I accidentally checked in my "gen" folder from an Android project (this folder contains the R.java generated class). When I realized I did this I deleted it from SVN and tried to ignore it. Now I am now getting the error... "Could not add gen to the ignore list! Working copy 'C:\code\guru' locked. When I try to run a cleanup command I get this... Cleanup failed to process the following paths: -C:\code\guru 'C:\code\guru\gen' is not a working copy directory. When I try to run a resolve I get this... Working copy 'C:\code\guru' locked Please execute the 'Cleanup' command. We are currently on SVN 1.6 on the server.

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  • MSBuild - setting a reference path

    - by Ryan
    I have several assemblies my project is dependant upon. These are stored in the Project's directory under the "Dependencies" folder. So something like this. Solution - Project - Dependancies FunkyAssembly.dll - bin - Debug - Release SomeCode.cs I've referenced FunkyAssembly.dll using Browse and in project.csproj I see <Reference Include="FunkyAssembly"> <HintPath>Dependancies\FunkyAssembly.dll</HintPath> </Reference> So far so good - except after a release build FunkyAssembly.dll is copied to the Release directory (not a problem in itself) but then future debug builds will reference this copy rather than the copy in Dependencies. You can see this if you at Path in the reference properties. This means that if Dependencies\FunkyAssembly.dll is updated the build won't pick it up as its referencing the old copy in bin/Release. Any way to FORCE the damn thing to pick up Dependencies\FunkyAssembly.dll rather than HINT?

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  • populating a list from another worksheet with 1 criteria

    - by Arcadian
    Hello, here is my dilemma. I have two worksheets one that has the name of clients and one that i want to copy the names to depending on the city. For instance: associated to each column is last name, first name and city. i have hundreds of names associated to different cities and what i would like is from worksheet1.xls to copy all the New York clients to worksheet2.xls either when i open worksheet2 or via macro what ever is easier and because last name is in one cell and the first name is in the other i would have to copy both. I saw that its possible to link cells from one worksheet to another and then do a vlookup depending on the criteria. Is that the best easiest way or is there another? thanks in advance and cheers oleg

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  • [change] Vlookup onto another workbook

    - by Arcadian
    Hello, here is my dilemma. I have two worksheets one that has the name of clients and one that i want to copy the names to depending on the city. For instance: associated to each column is last name, first name and city. i have hundreds of names associated to different cities and what i would like is from worksheet1.xls to copy all the New York clients to worksheet2.xls either when i open worksheet2 or via macro what ever is easier and because last name is in one cell and the first name is in the other i would have to copy both. I saw that its possible to link cells from one worksheet to another and then do a vlookup depending on the criteria. Is that the best easiest way or is there another? thanks in advance and cheers oleg

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  • Install TurboGears on windows xp

    - by coder
    I've been trying to get TurboGears installed on Windows by following this site. I've installed virtualenv but when I execute the command "virtualenv --no-site-packages testproj", I get the following message: New python executable in testproj\Scripts\python.exe Traceback (most recent call last): File "C:\Python26\Scripts\virtualenv-script.py", line 8, in load_entry_point('virtualenv==1.4.5', 'console_scripts', 'virtualenv')() File "C:\Python26\lib\site-packages\virtualenv-1.4.5-py2.6.egg\virtualenv.py", line 529, in main use_distribute=options.use_distribute) File "C:\Python26\lib\site-packages\virtualenv-1.4.5-py2.6.egg\virtualenv.py", line 612, in create_environment site_packages=site_packages, clear=clear)) File "C:\Python26\lib\site-packages\virtualenv-1.4.5-py2.6.egg\virtualenv.py", line 837, in install_python stdout=subprocess.PIPE) File "C:\Python26\lib\subprocess.py", line 621, in __init__ errread, errwrite) File "C:\Python26\lib\subprocess.py", line 830, in _execute_child startupinfo) WindowsError: [Error 14001] This application has failed to start because the application configuration is incorrect. Reinstalling the application may fix this problem Can someone help me debug this ? If any one knows a better tutorial to install turbogears, please let me know.

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  • .net List<string>.Remove bug Should I submit a MS Connect bug report on this?

    - by Dean Lunz
    So I was beating my head against a wall for a while before it dawned on me. I have some code that saves a list of names into a text file ala ... System.IO.File.WriteAllLines(dlg.FileName, this.characterNameMasterList.Distinct().ToArray()); The character names can contain special characters. These names come from the wow armory at www.wowarmory.com There are about 26000 names or so saved in the .txt file. The names get saved to the .txt file just fine. I wrote another application that reads these names from that .txt file using this code // download the names from the db var webNames = this.DownloadNames("character"); // filter names and get ones that need to be added to the db var localNames = new List<string>(System.IO.File.ReadAllLines(dlg.FileName)); foreach (var name in webNames) { if (localNames.Contains(name.Trim())) localNames.Remove(name); } return localNames; ... the code downloads a list of names from my website that are already in the db. Then reads the local .txt file and singles out every name that is not yet in the db so it can later add it. The names that get read from the .txt file also get read just fine with no problems. The problem comes in when removing names from the localNames list. localNames is a List type. As soon as localNames.Remove(name) gets called any names in the list that had special characters in them would get corrupted and be converted into ? characters. See for screen cap http://yfrog.com/12badcharsp So i tried doing it another way using ... // download the names from web that are already in the db var webNames = this.DownloadNames("character"); // filter names and get ones that need to be added to the db var localNames = new List<string>(System.IO.File.ReadAllLines(dlg.FileName)); int index = 0; while (index < webNames.Count) { var name = webNames[index++]; var pos = localNames.IndexOf(name.Trim()); if (pos != -1) localNames.RemoveAt(pos); } return localNames; .. But using localNames.RemoveAt also corrupts the items in the list converting special characters into ?. So is this a known bug with the List.remove methods? Does anyone know? Has anyone else had this problem? I also used .NET Reflector to disassemble/inspect the list.remove and list.RemoveAt code and it appear to be calling some external Copy function. Aside from the fact that this is prob not the best way to get a unique list of items from 2 lists am I missing something or should be aware of when using the List.Remove methods ? I am running windows 7 vs2010 and my app is set for .net 4 (no client profile )

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  • Java: JAX-WS passing authentication info to a call to webservice

    - by agnieszka
    I am using JAX-WS. I am connecting to .NET webservice that requires authentication. I first call the Authentication.asmx so that I can be authenticated. The call returns me a LoginResult that contains a cookie name. Then I call another webservice and I need to somehow pass this cookie or a cookie name. and I don't know how. Here is the code: //first service that returns login information Authentication auth = new Authentication(new URL("the_url"), new QName("http://schemas.microsoft.com/sharepoint/soap/", "Authentication")); LoginResult result = auth.getAuthenticationSoap().login(HTTPuserName, HTTPpassword); //i need to pass cookie or cookie name or any other login information to call to this service Copy copyService = new Copy(new URL("service_url"), new QName("http://schemas.microsoft.com/sharepoint/soap/", "Copy")); BindingProvider p = (BindingProvider) copyService.getCopySoap();

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  • resolve maya crash

    - by knishua
    Hi, I have a file which is crashing while rendering. File contains 50+ reference nodes. polycount : (lks)2,59,49,150; textures : (ths)2,628. It is being rendered in mental ray. All textures are .map. The attached image has the machine cofiguration with page file. here is the log file when the file crashes. what is the line in the log file mean. How to solve this. Exception code: C0000006: IN_PAGE_ERROR Fault address: 7814E420 in C:\WINDOWS\WinSxS\amd64_Microsoft.VC80.CRT_1fc8b3b 9a1e18e3b_8.0.50727.762_x-ww_9D1C6CE0\MSVCR80.dll what does the above mean. how to resolve this. Brgds, kNish

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  • Writing simple flash plugin for flowplayer

    - by danwoods
    Hello all, I'm trying to write a simple plugin for the flash player flowplayer (documentation for writing a plugin for flowplayer can be found here). I'm new to flash and I think I'm having a problem connecting the .fla file to the .as file when compiling into a .swf. As it is, when I include the plugin, the player doesn't show up. I've set the .fla's document class to the .as file and added the .as file to the .fla's publishing classpath. The .as file can be found here and the .fla file can be found here Any ideas?

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  • How to improve INSERT INTO ... SELECT locking behavior

    - by Artem
    In our production database, we ran the following pseudo-code SQL batch query running every hour: INSERT INTO TemporaryTable (SELECT FROM HighlyContentiousTableInInnoDb WHERE allKindsOfComplexConditions are true) Now this query itself does not need to be fast, but I noticed it was locking up HighlyContentiousTableInInnoDb, even though it was just reading from it. Which was making some other very simple queries take ~25 seconds (that's how long that other query takes). Then I discovered that InnoDB tables in such a case are actually locked by a SELECT! http://www.mysqlperformanceblog.com/2006/07/12/insert-into-select-performance-with-innodb-tables/ But I don't really like the solution in the article of selecting into an OUTFILE, it seems like a hack (temporary files on filesystem seem sucky). Any other ideas? Is there a way to make a full copy of an InnoDB table without locking it in this way during the copy. Then I could just copy the HighlyContentiousTable to another table and do the query there.

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  • Testing a Django view cause "AttributeError: 'NoneType' object has no attribute 'handler500'" error

    - by jack
    I just wanted to start testing a Django view using the code below: from django.test.client import Client c = Client() response = c.get('/search/keyword') print response.content It just throws out following error message: "/usr/local/lib/python2.6/dist-packages/django/test/client.py", line 286, in get response = self.request(**r) File "/usr/local/lib/python2.6/dist-packages/django/test/client.py", line 230, in request response = self.handler(environ) File "/usr/local/lib/python2.6/dist-packages/django/test/client.py", line 74, in __call__ response = self.get_response(request) File "/usr/local/lib/python2.6/dist-packages/django/core/handlers/base.py", line 143, in get_response return self.handle_uncaught_exception(request, resolver, exc_info) File "/usr/local/lib/python2.6/dist-packages/django/core/handlers/base.py", line 178, in handle_uncaught_exception callback, param_dict = resolver.resolve500() File "/usr/local/lib/python2.6/dist-packages/django/core/urlresolvers.py", line 268, in resolve500 return self._resolve_special('500') File "/usr/local/lib/python2.6/dist-packages/django/core/urlresolvers.py", line 258, in _resolve_special callback = getattr(self.urlconf_module, 'handler%s' % view_type) AttributeError: 'NoneType' object has no attribute 'handler500' The view works in browser. What's wrong with above code?

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  • Is it a good idea to create an STL iterator which is noncopyable?

    - by BillyONeal
    Most of the time, STL iterators are CopyConstructable, because several STL algorithms require this to improve performance, such as std::sort. However, I've been working on a pet project to wrap the FindXFile API (previously asked about), but the problem is it's impossible to implement a copyable iterator around this API. A find handle cannot be duplicated by any means -- DuplicateHandle specifically forbids passing handles to it. And if you just maintain a reference count to the find handle, then a single increment by any copy results in an increment of all copies -- clearly that is not what a copy constructed iterator is supposed to do. Since I can't satisfy the traditional copy constructible requirement for iterators here, is it even worth trying to create an "STL style" iterator? On one hand, creating some other enumeration method is going to not fall into normal STL conventions, but on the other, following STL conventions are going to confuse users of this iterator if they try to CopyConstruct it later. Which is the lesser of two evils?

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