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• Using Zend Framework and Doctrine with independend modular structures

  - by stefax

  I've seen a lot of articles about integrating ZF and Doctrine. There is also a proposal for ZF here but they have always two possible structures. Either they put all models into one top level model directory or they put it into a module related model directory. application |-- Bootstrap.php |-- configs |-- controllers |-- models - EITHER HERE |-- modules | -- examplemodule | |-- controllers | |-- models - OR HERE | |-- views |-- views For our projects I see problems for either of the two options: 1. One directory: application/models - in a complex system after a short time there will be hundreds of files, over all when you have the table classes two (e.g. User.php and UserTable.php). 2. Module based model directories: application/modules/examplemodule/models - in many cases we use models in multiple modules at the same time. So the "User" is required e.g. in the modules "game", "administration", ... Is there a way to use some kind of sub directories under the top level directory "models" to get some grouping. It should be completely independent of the module structure. application |-- Bootstrap.php ... |-- models | -- user | |-- User.php | |-- Friend.php | |-- other user related models | -- game | |-- Game.php | |-- Score.php | |-- ... ... Any solution should support autoloading and the class generation from yaml files. Any ideas, links or solutions? Thanks!

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• Alright, I'm still stuck on this homework problem. C++

  - by Josh

  Okay, the past few days I have been trying to get some input on my programs. Well I decided to scrap them for the most part and try again. So once again, I'm in need of help. For the first program I'm trying to fix, it needs to show the sum of SEVEN numbers. Well, I'm trying to change is so that I don't need the mem[##] = ####. I just want the user to be able to input the numbers and the program run from there and go through my switch loop. And have some kind of display..saying like the sum is?.. Here's my code so far. #include <iostream> #include <iomanip> #include <ios> using namespace std; int main() { const int READ = 10; const int WRITE = 11; const int LOAD = 20; const int STORE = 21; const int ADD = 30; const int SUBTRACT = 31; const int DIVIDE = 32; const int MULTIPLY = 33; const int BRANCH = 40; const int BRANCHNEG = 41; const int BRANCHZERO = 42; const int HALT = 43; int mem[100] = {0}; //Making it 100, since simpletron contains a 100 word mem. int operation; //taking the rest of these variables straight out of the book seeing as how they were italisized. int operand; int accum = 0; // the special register is starting at 0 int counter; for ( counter=0; counter < 100; counter++) mem[counter] = 0; // This is for part a, it will take in positive variables in //a sent-controlled loop and compute + print their sum. Variables from example in text. mem[0] = 1009; mem[1] = 1109; mem[2] = 2010; mem[3] = 2111; mem[4] = 2011; mem[5] = 3100; mem[6] = 2113; mem[7] = 1113; mem[8] = 4300; counter = 0; //Makes the variable counter start at 0. while(true) { operand = mem[ counter ]%100; // Finds the op codes from the limit on the mem (100) operation = mem[ counter ]/100; //using a switch loop to set up the loops for the cases switch ( operation ){ case READ: //reads a variable into a word from loc. Enter in -1 to exit cout <<"\n Input a positive variable: "; cin >> mem[ operand ]; counter++; break; case WRITE: // takes a word from location cout << "\n\nThe content at location " << operand << " is " << mem[operand]; counter++; break; case LOAD:// loads accum = mem[ operand ];counter++; break; case STORE: //stores mem[ operand ] = accum;counter++; break; case ADD: //adds accum += mem[operand];counter++; break; case SUBTRACT: // subtracts accum-= mem[ operand ];counter++; break; case DIVIDE: //divides accum /=(mem[ operand ]);counter++; break; case MULTIPLY: // multiplies accum*= mem [ operand ];counter++; break; case BRANCH: // Branches to location counter = operand; break; case BRANCHNEG: //branches if acc. is < 0 if (accum < 0) counter = operand; else counter++; break; case BRANCHZERO: //branches if acc = 0 if (accum == 0) counter = operand; else counter++; break; case HALT: // Program ends break; } } return 0; } part B int main() { const int READ = 10; const int WRITE = 11; const int LOAD = 20; const int STORE = 21; const int ADD = 30; const int SUBTRACT = 31; const int DIVIDE = 32; const int MULTIPLY = 33; const int BRANCH = 40; const int BRANCHNEG = 41; const int BRANCHZERO = 41; const int HALT = 43; int mem[100] = {0}; int operation; int operand; int accum = 0; int pos = 0; int j; mem[22] = 7; // loop 7 times mem[25] = 1; // increment by 1 mem[00] = 4306; mem[01] = 2303; mem[02] = 3402; mem[03] = 6410; mem[04] = 3412; mem[05] = 2111; mem[06] = 2002; mem[07] = 2312; mem[08] = 4210; mem[09] = 2109; mem[10] = 4001; mem[11] = 2015; mem[12] = 3212; mem[13] = 2116; mem[14] = 1101; mem[15] = 1116; mem[16] = 4300; j = 0; while ( true ) { operand = memory[ j ]%100; // Finds the op codes from the limit on the memory (100) operation = memory[ j ]/100; //using a switch loop to set up the loops for the cases switch ( operation ){ case 1: //reads a variable into a word from loc. Enter in -1 to exit cout <<"\n enter #: "; cin >> memory[ operand ]; break; case 2: // takes a word from location cout << "\n\nThe content at location " << operand << "is " << memory[operand]; break; case 3:// loads accum = memory[ operand ]; break; case 4: //stores memory[ operand ] = accum; break; case 5: //adds accum += mem[operand];; break; case 6: // subtracts accum-= memory[ operand ]; break; case 7: //divides accum /=(memory[ operand ]); break; case 8: // multiplies accum*= memory [ operand ]; break; case 9: // Branches to location j = operand; break; case 10: //branches if acc. is < 0 break; case 11: //branches if acc = 0 if (accum == 0) j = operand; break; case 12: // Program ends exit(0); break; } j++; } return 0; }

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• Why is Collection<String>.class Illegal?

  - by Peter

  I am puzzled by generics. You can declare a field like: Class<Collection<String>> clazz = ... It seems logical that you could assign this field with: Class<Collection<String>> clazz = Collection<String>.class; However, this generates an error: Syntax error on token ">", void expected after this token So it looks like the .class operator does not work with generics. So I tried: class A<S> {} class B extends A<String> {} Class<A<String>> c = B.class; Also does not work, generates: Type mismatch: cannot convert from Class<Test.StringCollection> to Class<Collection<String>> Now, I really fail to see why this should not work. I know generic types are not reified but in both cases it seems to be fully type safe without having access to runtime generic types. Anybody an idea? Peter Kriens

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• Why Spark viewengine renders unnecessary (or unexpected) quotes?

  - by Arnis L.

  If i add pageBaseType="Spark.Web.Mvc.SparkView" in my web.config (necessary to fix intellisense), somehow it does not render links (probably not only) correctly anymore. This is how it's supposed to look like (and does, if page base type is not specified)= This is how it looks when base type is specified= Chrome source viewer shows identical page source code for both cases= <body> <div class="content"> <div class="navigation"> <a href="/Employee/List">Employees</a> <a href="/Product/List">Products</a> <a href="/Store/List">Stores</a> <div class="navigation_title"> Navigation</div> </div> <div class="main"> <div class="content"> <h2>Employees</h2>Nothing found... &lt;a href=&quot;/Employee/Create&quot;&gt;Create&lt;/a&gt; </div> </div> </div> </body> Developer tools does not= So - why my link gets htmlencoded (if that's what happens)? If it's default behavior, then how to render raw html? Using latest Spark version, rebuilt with Asp.Net Mvc2 RC assemblies.

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• Syncing two separate structures to the same master data

  - by Mike Burton

  I've got multiple structures to maintain in my application. All link to the same records, and one of them could be considered the "master" in that it reflects actual relationships held in files on disk. The other structures are used to "call out" elements of the main design for purchase and work orders. I'm struggling to come up with a pattern that deals appropriately with changes to the master data. As an example, the following trees might refer to the same data: A |_ B |_ C |_ D |_ E |_ B |_ C |_ D A |_ B E C |_ D A |_ B C D E These secondary structures follow internal rules, but their overall structure is usually user-determined. In all cases (including the master), any element can be used in multiple locations and in multiple trees. When I add a child to any element in the tree, I want to either automatically build the secondary structure for each instance of the "master" element or at least advertise the situation to the user and allow them to manually generate the data required for the secondary trees. Is there any pattern which might apply to this situation? I've been treating it as a view problem, but it turns out to be more complicated than that when you look at the initial generation of the data.

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• Factory Girl: Automatically assigning parent objects

  - by Ben Scheirman

  I'm just getting into Factory Girl and I am running into a difficulty that I'm sure should be much easier. I just couldn't twist the documentation into a working example. Assume I have the following models: class League < ActiveRecord::Base has_many :teams end class Team < ActiveRecord::Base belongs_to :league has_many :players end class Player < ActiveRecord::Base belongs_to :team end What I want to do is this: team = Factory.build(:team_with_players) and have it build up a bunch of players for me. I tried this: Factory.define :team_with_players, :class => :team do |t| t.sequence {|n| "team-#{n}" } t.players {|p| 25.times {Factory.build(:player, :team => t)} } end But this fails on the :team=>t section, because t isn't really a Team, it's a Factory::Proxy::Builder. I have to have a team assigned to a player. In some cases I want to build up a League and have it do a similar thing, creating multiple teams with multiple players. What am I missing?

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• Measuring execution time of selected loops

  - by user95281

  I want to measure the running times of selected loops in a C program so as to see what percentage of the total time for executing the program (on linux) is spent in these loops. I should be able to specify the loops for which the performance should be measured. I have tried out several tools (vtune, hpctoolkit, oprofile) in the last few days and none of them seem to do this. They all find the performance bottlenecks and just show the time for those. Thats because these tools only store the time taken that is above a threshold (~1ms). So if one loop takes lesser time than that then its execution time won't be reported. The basic block counting feature of gprof depends on a feature in older compilers thats not supported now. I could manually write a simple timer using gettimeofday or something like that but for some cases it won't give accurate results. For ex: for (i = 0; i < 1000; ++i) { for (j = 0; j < N; ++j) { //do some work here } } Now here I want to measure the total time spent in the inner loop and I will have to put a call to gettimeofday inside the first loop. So gettimeofday itself will get called a 1000 times which introduces its own overhead and the result will be inaccurate.

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• iPhone OS: Strategies for high density image work

  - by Jasconius

  I have a project that is coming around the bend this summer that is going to involve, potentially, an extremely high volume of image data for display. We are talking hundreds of 640x480-ish images in a given application session (scaled to a smaller resolution when displayed), and handfuls of very large (1280x1024 or higher) images at a time. I've already done some preliminary work and I've found that the typical 640x480ish image is just a shade under 1MB in memory when placed into a UIImageView and displayed... but the very large images can be a whopping 5+ MB's in some cases. This project is actually be targeted at the iPad, which, in my Instruments tests seems to cap out at about 80-100MB's of addressable physical memory. Details aside, I need to start thinking of how to move huge volumes of image data between virtual and physical memory while preserving the fluidity and responsiveness of the application, which will be high visibility. I'm probably on the higher ends of intermediate at Objective-C... so I am looking for some solid articles and advice on the following: 1) Responsible management of UIImage and UIImageView in the name of conserving physical RAM 2) Merits of using CGImage over UIImage, particularly for the huge images, and if there will be any performance gain 3) Anything dealing with memory paging particularly as it pertains to images I will epilogue by saying that the numbers I have above maybe off by about 10 or 15%. Images may or may not end up being bundled into the actual app itself as opposed to being loaded in from an external server.

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• Writing language converter in ANTLR

  - by Stefan

  I'm writing a converter between some dialects of the same programming language. I've found a grammar on the net - it's complex and handles all the cases. Now I'm trying to write the appropriate actions. Most of the input is just going to be rewritten to output. What I need to do is parse function calls, do my magic (rename function, reorder arguments, etc) and write it. I'm using AST as output. When I come across a function call, I build a custom object structure (from classes defined in my target language), call the appropriate function and I have a string that represents the transformed function that I want to get. The problem is, what I'm supposed to do with that string? I'd like to replace the .text attribute of the enclosing rule, but setText() is only available on lexer rules and the rule's .text attribute is read-only. How to solve this problem? program : statement_list { output = $statement_list.text; } ; //... statement : expression_statement // ... ; expression_statement : function_call // ... ; function_call : ID '(' { /* build the object, assign name */ Function function = new Function(); //... } ( arg1 = expression { /* add first parameter */ } ( ',' arg2 = expression { /* add the rest of parameters */ } )* )? ')' { /* convert the function call */ string converted = Tools.Convert(function); // $setText(converted); // doesn't work // $functionCall.text = converted; // doesn't work } ;

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• Match entities fulfilling filter (strict superset of search)

  - by Jon

  I have an entity (let's say Person) with a set of arbitrary attributes with a known subset of values. I need to search for all of these entities that match all my filter conditions. That is, given a set of Attributes A, I need to find all people that have a set of Attributes that are a superset of A. For example, my table structures look like this: Person: id | name 1 | John Doe 2 | Jane Roe 3 | John Smith Attribute: id | attr_name 1 | Sex 2 | Eye Color ValidValue: id | attr_id | value_name 1 | 1 | Male 2 | 1 | Female 3 | 2 | Blue 4 | 2 | Green 5 | 2 | Brown PersonAttributes id | person_id | attr_id | value_id 1 | 1 | 1 | 1 2 | 1 | 2 | 3 3 | 2 | 1 | 2 4 | 2 | 2 | 4 5 | 3 | 1 | 1 6 | 3 | 2 | 4 In JPA, I have entities built for all of these tables. What I'd like to do is perform a search for all entities matching a given set of attribute-value pairs. For instance, I'd like to be able to find all males (John Doe and John Smith), all people with green eyes (Jane Roe or John Smith), or all females with green eyes (Jane Roe). I see that I can already take advantage of the fact that I only really need to match on value_id, since that's already unique and tied to the attr_id. But where can I go from there? I've been trying to do something like the following, given that the ValidValue is unique in all cases: select distinct p from Person p join p.personAttributes a where a.value IN (:values) Then I've tried putting my set of required values in as "values", but that gives me errors no matter how I try to structure that. I also have to get a little more complicated, as follows, but at this point I'd be happy with solving the first problem cleanly. However, if it's possible, the Attribute table actually has a field for default value: id | attr_name | default_value 1 | Sex | 1 2 | Eye Color | 5 If the value you're searching on happens to be the default value, I want it to return any people that have no explicit value set for that attribute, because in the application logic, that means they inherit the default value. Again, I'm more concerned about the primary question, but if someone who can help with that also has some idea of how to do this one, I'd be extremely grateful.

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• Getting value of "i" from GEvent

  - by Cosizzle

  Hello, I'm trying to add an event listener to each icon on the map when it's pressed. I'm storing the information in the database and the value that I'm wanting to retrive is "i" however when I output "i", I get it's last value which is 5 (there are 6 objects being drawn onto the map) Below is the code, what would be the best way to get the value of i, and not the object itself. var drawLotLoc = function(id) { var lotLoc = new GIcon(G_DEFAULT_ICON); // create icon object lotLoc.image = url+"images/markers/lotLocation.gif"; // set the icon image lotLoc.shadow = ""; // no shadow lotLoc.iconSize = new GSize(24, 24); // set the size var markerOptions = { icon: lotLoc }; $.post(opts.postScript, {action: 'drawlotLoc', id: id}, function(data) { var markers = new Array(); // lotLoc[x].description // lotLoc[x].lat // lotLoc[x].lng // lotLoc[x].nighbourhood // lotLoc[x].lot var lotLoc = $.evalJSON(data); for(var i=0; i<lotLoc.length; i++) { var spLat = parseFloat(lotLoc[i].lat); var spLng = parseFloat(lotLoc[i].lng); var latlng = new GLatLng(spLat, spLng) markers[i] = new GMarker(latlng, markerOptions); myMap.addOverlay(markers[i]); GEvent.addListener(markers[i], "click", function() { console.log(i); // returning 5 in all cases. // I _need_ this to be unique to the object being clicked. console.log(this); }); } });

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• Can a class inherit from LambdaExpression in .NET? Or is this not recommended?

  - by d.

  Consider the following code (C# 4.0): public class Foo : LambdaExpression { } This throws the following design-time error: Foo does not implement inherited abstract member System.Linq.Expressions.LambdaExpression.Accept(System.Linq.Expressions.Compiler.StackSpiller) There's absolutely no problem with public class Foo : Expression { } but, out of curiosity and for the sake of learning, I've searched in Google System.Linq.Expressions.LambdaExpression.Accept(System.Linq.Expressions.Compiler.StackSpiller) and guess what: zero results returned (when was the last time you saw that?). Needless to say, I haven't found any documentation on this method anywhere else. As I said, one can easily inherit from Expression; on the other hand LambdaExpression, while not marked as sealed (Expression<TDelegate> inherits from it), seems to be designed to prevent inheriting from it. Is this actually the case? Does anyone out there know what this method is about? EDIT (1): More info based on the first answers - If you try to implement Accept, the editor (C# 2010 Express) automatically gives you the following stub: protected override Expression Accept(System.Linq.Expressions.ExpressionVisitor visitor) { return base.Accept(visitor); } But you still get the same error. If you try to use a parameter of type StackSpiller directly, the compiler throws a different error: System.Linq.Expressions.Compiler.StackSpiller is inaccessible due to its protection level. EDIT (2): Based on other answers, inheriting from LambdaExpression is not possible so the question as to whether or not it is recommended becomes irrelevant. I wonder if, in cases like this, the error message should be Foo cannot implement inherited abstract member System.Linq.Expressions.LambdaExpression.Accept(System.Linq.Expressions.Compiler.StackSpiller) because [reasons go here]; the current error message (as some answers prove) seems to tell me that all I need to do is implement Accept (which I can't do).

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• How should I unit test a code-generator?

  - by jkp

  This is a difficult and open-ended question I know, but I thought I'd throw it to the floor and see if anyone had any interesting suggestions. I have developed a code-generator that takes our python interface to our C++ code (generated via SWIG) and generates code needed to expose this as WebServices. When I developed this code I did it using TDD, but I've found my tests to be brittle as hell. Because each test essentially wanted to verify that for a given bit of input code (which happens to be a C++ header) I'd get a given bit of outputted code I wrote a small engine that reads test definitions from XML input files and generates test cases from these expectations. The problem is I dread going in to modify the code at all. That and the fact that the unit tests themselves are a: complex, and b: brittle. So I'm trying to think of alternative approaches to this problem, and it strikes me I'm perhaps tackling it the wrong way. Maybe I need to focus more on the outcome, IE: does the code I generate actually run and do what I want it to, rather than, does the code look the way I want it to. Has anyone got any experiences of something similar to this they would care to share?

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• System.OutOfMemoryException was thrown. at Go60505(RegexRunner ) at System.Text.RegularExpressions.C

  - by Deanvr

  Hi All, I am a c# dev working on some code for a website in vb.net. We use a lot of caching on a 32bit iss 6 win 2003 box and in some cases run into OutOfMemoryException exceptions. This is the code I trace it back to and would like to know if anyone else has has this... Public Sub CreateQueryStringNodes() 'Check for nonstandard characters' Dim key As String Dim keyReplaceSpaces As String Dim r As New Regex("^[-a-zA-Z0-9_]+$", RegexOptions.Compiled) For Each key In HttpContext.Current.Request.Form If Not IsNothing(key) Then keyReplaceSpaces = key.Replace(" ", "_") If r.IsMatch(keyReplaceSpaces) Then CreateNode(keyReplaceSpaces, HttpContext.Current.Request(key)) End If End If Next For Each key In HttpContext.Current.Request.QueryString If Not IsNothing(key) Then keyReplaceSpaces = key.Replace(" ", "_") If r.IsMatch(keyReplaceSpaces) Then CreateNode(keyReplaceSpaces, HttpContext.Current.Request(key).Replace("--", "-")) End If End If Next End Sub .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053 error: Exception of type 'System.OutOfMemoryException' was thrown. at Go60505(RegexRunner ) at System.Text.RegularExpressions.CompiledRegexRunner.Go() at System.Text.RegularExpressions.RegexRunner.Scan(Regex regex, String text, Int32 textbeg, Int32 textend, Int32 textstart, Int32 prevlen, Boolean quick) at System.Text.RegularExpressions.Regex.Run(Boolean quick, Int32 prevlen, String input, Int32 beginning, Int32 length, Int32 startat) at System.Text.RegularExpressions.Regex.IsMatch(String input) at Xcite.Core.XML.Write.CreateQueryStringNodes() at Xcite.Core.XML.Write..ctor(String IncludeSessionAndPostedData) at mysite._Default.Page_Load(Object sender, EventArgs e) at System.Web.UI.Control.OnLoad(EventArgs e) at System.Web.UI.Control.LoadRecursive() at thanks

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• Can Haskell's Parsec library be used to implement a recursive descent parser with backup?

  - by Thor Thurn

  I've been considering using Haskell's Parsec parsing library to parse a subset of Java as a recursive descent parser as an alternative to more traditional parser-generator solutions like Happy. Parsec seems very easy to use, and parse speed is definitely not a factor for me. I'm wondering, though, if it's possible to implement "backup" with Parsec, a technique which finds the correct production to use by trying each one in turn. For a simple example, consider the very start of the JLS Java grammar: Literal: IntegerLiteral FloatingPointLiteral I'd like a way to not have to figure out how I should order these two rules to get the parse to succeed. As it stands, a naive implementation like this: literal = do { x <- try (do { v <- integer; return (IntLiteral v)}) <|> (do { v <- float; return (FPLiteral v)}); return(Literal x) } Will not work... inputs like "15.2" will cause the integer parser to succeed first, and then the whole thing will choke on the "." symbol. In this case, of course, it's obvious that you can solve the problem by re-ordering the two productions. In the general case, though, finding things like this is going to be a nightmare, and it's very likely that I'll miss some cases. Ideally, I'd like a way to have Parsec figure out stuff like this for me. Is this possible, or am I simply trying to do too much with the library? The Parsec documentation claims that it can "parse context-sensitive, infinite look-ahead grammars", so it seems like something like I should be able to do something here.

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• How to reliably replace a library-defined error handler with my own?

  - by sharptooth

  On certain error cases ATL invokes AtlThrow() which is implemented as ATL::AtlThrowImpl() which in turn throws CAtlException. The latter is not very good - CAtlException is not even derived from std::exception and also we use our own exceptions hierarchy and now we will have to catch CAtlException separately here and there which is lots of extra code and error-prone. Looks like it is possible to replace ATL::AtlThrowImpl() with my own handler - define _ATL_CUSTOM_THROW and define AtlThrow() to be the custom handler before including atlbase.h - and ATL will call the custom handler. Not so easy. Some of ATL code is not in sources - it comes compiled as a library - either static or dynamic. We use the static - atls.lib. And... it is compiled in such way that it has ATL::ThrowImpl() inside and some code calling it. I used a static analysis tool - it clearly shows that there're paths on which the old default handler is called. To ensure I even tried to "reimplement" ATL::AtlThrowImpl() in my code. Now the linker says it sees two declarations of ATL::AtlThrowImpl() which I suppose confirms that there's another implementation that can be called by some code. How can I handle this? How do I replace the default handler completely and ensure that the default handler is never called?

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• WPF : Multiple views, one DataContext

  - by zapho

  Hi, I'm working on a WPF application which must handle multiple screens (two at this this time). One view can be opened on several screens and user actions must be reflected consistently on all screens. To achieve this, for a given type of view, a single DataContext is instantiated. Then, when a view is displayed on a screen, the unique DataContext is attached to it. So, one DataContext, several views (same type of view/xaml). So far so good. It works quite well in most cases. I do have a problem with a specific view which relies on ItemsControl. These ItemsControl are used to display UIElements dynamically build in the ViewModel/DataContext (C# code). These UIElements are mostly Path objects. Example : <ItemsControl ItemsSource="{Binding WindVectors}"> <ItemsControl.Template> <ControlTemplate TargetType="{x:Type ItemsControl}"> <Canvas IsItemsHost="True" /> </ControlTemplate> </ItemsControl.Template> </ItemsControl> Here, WindVectors is a ObservableCollection<UIElement>. When the view is opened the first time, everything is fine. The problem is that when the view is opened one another screen, all ItemsControl are removed from the first screen and displayed one the second screen. Other WPF components (TextBlock for instance) on this view react normally and are displayed on both screens. Any help would be greatly appreciated. Thanks. Fabrice

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• How can I work around the fact that in C++, sin(M_PI) is not 0?

  - by Adam Doyle

  In C++, const double Pi = 3.14159265; cout << sin(Pi); // displays: 3.58979e-009 it SHOULD display the number zero I understand this is because Pi is being approximated, but is there any way I can have a value of Pi hardcoded into my program that will return 0 for sin(Pi)? (a different constant maybe?) In case you're wondering what I'm trying to do: I'm converting polar to rectangular, and while there are some printf() tricks I can do to print it as "0.00", it still doesn't consistently return decent values (in some cases I get "-0.00") The lines that require sin and cosine are: x = r*sin(theta); y = r*cos(theta); BTW: My Rectangular - Polar is working fine... it's just the Polar - Rectangular Thanks! edit: I'm looking for a workaround so that I can print sin(some multiple of Pi) as a nice round number to the console (ideally without a thousand if-statements) edit: In case anyone's curious, this was what I landed on: double sin2(double theta) // in degrees { double s = sin(toRadians(theta)); if (fabs(s - (int)s) < 0.000001) { return floor(s + 0.5); } return s; } where toRadians() is a macro that converts to radians

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• How can use the currently displayed node to filter a block-level view on that node's page?

  - by Deane

  I have parent/child relationship set up via Node Reference. A Child record can have a Parent record selected from a Node Reference field (this is optional -- I can have Parent-less Children as well). I've created a Views block to appear on the Parent pages, below the content. It's going to show a table of all the Child nodes for that Parent. Problem is, right now it shows every Child node. I need to filter it for just the Parent being displayed. What I need to be able to do is add a filter to this View to effectively say, "Only show the Child nodes that are assigned to the Parent being displayed on this page." So, somehow I need to be able to get the Nid of the currently displaying node (which will be a Parent, in all cases when this block is displayed), and use that in a filter in my View. How exactly can I do this? (Initially I used an attachment view for this (as this page instructs). I created a page view to display the Parent, then an attachment view to display all the Children, then attached that under the page view. This worked, but it was almost absurdly complicated to set up, and it was an undesirable for a number of other reasons -- primarily that my Parent now has two dedicated URLs, it's own node-level page, and the similar page created by this view.) Using Drupal 6.15.

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• Rolling Back a Transaction with MySQL Connector in VB.net

  - by Jonathan

  Hey all- I have one multi-row INSERT statement (300 or so sets of values) that I would like to commit to the MySQL database in an all-or-nothing fashion. insert into table VALUES (1, 2, 3), (4, 5, 6), (7, 8, 9); In some cases, a set of values in the command will not meet the criteria of the table (duplicate key, for example). When that happens I do not want any of the previous sets added to the database. I've implemented this with the following code, however, my rollback command doesn't appear to be making a difference. I've used this documentation: http://dev.mysql.com/doc/refman/5.0/es/connector-net-examples-mysqltransaction.html Dim transaction As MySqlTransaction = sqlConnection.BeginTransaction() sqlCommand = New MySqlCommand(insertStr, sqlConnection, transaction) Try sqlCommand.ExecuteNonQuery() Catch ex As Exception writeToLog("EXCEPTION: " & ex.Message & vbNewLine) writeToLog("Could not execute " & sqlCmd & vbNewLine) Try transaction.Rollback() writeToLog("All statements were rolled back." & vbNewLine) Return False Catch rollbackEx As Exception writeToLog("EXCEPTION: " & rollbackEx.Message & vbNewLine) writeToLog("All statements were not rolled back." & vbNewLine) Return False End Try End Try transaction.commit() I get the DUPLICATE KEY exception thrown, no Rollback Exception thrown, and every set of values up to duplicate key committed to the database. What am I doing wrong? Thanks- Jonathan

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• Ember model is gone when I use the renderTemplate hook

  - by Mickael Caruso

  I have a single template - editPerson.hbs <form role="form"> FirstName: {{input type="text" value=model.firstName }} <br/> LastName: {{input type="text" value=model.lastName }} </form> I want to render this template when the user wants to edit an existing person or create a new person. So, I set up routes: App.Router.map(function(){ this.route("createPerson", { path: "/person/new" }); this.route("editPerson", { path: "/person/:id}); // other routes not show for brevity }); So, I define two routes - one for create and one for edit: App.CreatePersonRoute = Ember.Route.extend({ renderTemplate: function(){ this.render("editPerson", { controller: "editPerson" }); }, model: function(){ return {firstName: "John", lastName: "Smith" }; } }); App.EditPersonRoute = Ember.Route.extend({ model: function(id){ return {firstName: "John Existing", lastName: "Smith Existing" }; } }); So, I hard-code the models. I'm concerned about the createPerson route. I'm telling it to render the editPersonTemplate and to use the editPerson controller (which I don't show because I don't think it matters - but I made one, though.) When I use renderTemplate, I lose the model John Smith, which in turn, won't display on the editTemplate on the web page. Why? I "fixed" this by creating a separate and identical (to editPerson.hbs) createPerson.hbs, and removing the renderTemplate hook in the CreatePerson. It works as expected, but I find it somewhat troubling to have a separate and identical template for the edit and create cases. I looked everywhere for how to properly do this, and I found no answers.

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• Why use INCLUDE in a SQL index

  - by StarLite

  I recently encountered an index in a database I maintain that was of the form: CREATE INDEX [IX_Foo] ON [Foo] ( Id ASC ) INCLUDE ( SubId ) In this particular case, the performance problem that I was encountering (a slow SELECT filtering on both Id and SubId) could be fixed by simply moving the SubId column into the index proper rather than as an included column. This got me thinking however that I don't understand the reasoning behind included columns at all, when generally, they could simply be a part of the index itself. Even if I don't particularly care about the items being in the index itself is there any downside to having column in the index rather than simply being included. After some research, I am aware that there are a number of restrictions on what can go into an indexed column (maximum width of the index, and some column types that can't be indexed like 'image'). In these cases I can see that you would be forced to include the column in the index page data. The only thing I can think of is that if there are updates on SubId, the row will not need to be relocated if the column is included (though the value in the index would need to be changed). Is there something else that I'm missing? I'm considering going through the other indexes in the database and shifting included columns in the index proper where possible. Would this be a mistake? I'm primarily interested in MS SQL Server, but information on other DB engines is welcome also.

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• malloc works, cudaHostAlloc segfaults?

  - by Mikhail

  I am new to CUDA and I want to use cudaHostAlloc. I was able to isolate my problem to this following code. Using malloc for host allocation works, using cudaHostAlloc results in a segfault, possibly because the area allocated is invalid? When I dump the pointer in both cases it is not null, so cudaHostAlloc returns something... works in_h = (int*) malloc(length*sizeof(int)); //works for (int i = 0;i<length;i++) in_h[i]=2; doesn't work cudaHostAlloc((void**)&in_h,length*sizeof(int),cudaHostAllocDefault); for (int i = 0;i<length;i++) in_h[i]=2; //segfaults Standalone Code #include <stdio.h> void checkDevice() { cudaDeviceProp info; int deviceName; cudaGetDevice(&deviceName); cudaGetDeviceProperties(&info,deviceName); if (!info.deviceOverlap) { printf("Compute device can't use streams and should be discared."); exit(EXIT_FAILURE); } } int main() { checkDevice(); int *in_h; const int length = 10000; cudaHostAlloc((void**)&in_h,length*sizeof(int),cudaHostAllocDefault); printf("segfault comming %d\n",in_h); for (int i = 0;i<length;i++) { in_h[i]=2; } free(in_h); return EXIT_SUCCESS; } ~ Invocation [id129]$ nvcc fun.cu [id129]$ ./a.out segfault comming 327641824 Segmentation fault (core dumped) Details Program is run in interactive mode on a cluster. I was told that an invocation of the program from the compute node pushes it to the cluster. Have not had any trouble with other home made toy cuda codes.

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• Copying a directory that is version controlled

  - by ibz

  I am curious whether it is OK to copy a directory that is under version control and start working on both copies. I know it can be different from one VCS to another, but I intentionally don't specify any VCS since I am curious about different cases. I was talking to a coworker recently about doing it in SVN. I think it should be OK, but I am still not 100% sure, since I don't know what exactly SVN is storing in the working copy. However, if we talk about the DVCS world, things might be even more unclear, since every working copy is a repository by itself. Being faced with doing this in bzr now, I decided to ask the question. Later edit: Some people asked why I would want to do that. Here is the whole story: In the case of SVN it was because being out of the office, the connection to the SVN server was really slow, so me and my coworker decided to check out the sources only once and make a local copy. That's what we did and it worked OK, but I am still wondering whether it is guaranteed to work, or it just happened. In the bzr case, I am planning to move the "main" repo to another server. So I was thinking to just copy it there and start considering that the main repo. I guess the safest is to make a clone though.

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• Stack Overflow when debugging application in iPhone simulator

  - by mjdth

  I'm getting this every time I attempt to debug my app in the simulator: [Session started at 2010-05-11 16:16:52 -0500.] GNU gdb 6.3.50-20050815 (Apple version gdb-1467) (Wed Apr 21 06:57:21 UTC 2010) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "x86_64-apple-darwin".sharedlibrary apply-load-rules all Attaching to process 51573. Program received signal: “EXC_BAD_ACCESS”. Data Formatters temporarily unavailable, will re-try after a 'continue'. (Cannot call into the loader at present, it is locked.) I've looked around and found a few similar cases, but they all seem to be related to a missing file and an extra necessary build phase. I'm getting no notification of a missing file here so I'm not sure where to start to fix this and get the app running again. Thanks for any insight!

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