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  • Problems with my JS array undefined x 7

    - by Dave
    I have an array im trying to loop through to create a new type of array specific to my current page. My array looks like this: //$_SESSION['data'] = Array ( [0] => 1 [1] => 0 [2] => Tom [8] => 1 [4] => 1 [5] => Array ( [7] => Array ( [0] => Andrew [1] => 1 [2] => 1 [4] => 0 [5] => avatar.jpg [6] => 1 ) ) [6] => Array ( [0] => 1 [1] => 2 ) ) So in my JS file i have this: var stats = <? echo $_SESSION['data'][5]); ?> ; //this is the array my_data = new Array(); for(var key in stats){ if(key in my_data){} else { //prevent double entry my_data[key] = new Array(); my_data[key][0] = stats[key][6]; my_data[key][1] = stats[key][5]; my_data[key][2] = stats[key][2]; my_data[key][3] = stats[key][0]; } } console.log(my_data); Now in console.log i get this : [undefined × 7, Array[4] 0: "1" 1: "avatar.jpg" 2: "1" 3: "Andrew" length: 4 __proto__: Array[0] ] I'm wondering why it is saying undefined x7?

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  • Is it advisable to have an interface as the return type?

    - by wb
    I have a set of classes with the same functions but with different logic. However, each class function can return a number of objects. It is safe to set the return type as the interface? Each class (all using the same interface) is doing this with different business logic. protected IMessage validateReturnType; <-- This is in an abstract class public bool IsValid() <-- This is in an abstract class { return (validateReturnType.GetType() == typeof(Success)); } public IMessage Validate() { if (name.Length < 5) { validateReturnType = new Error("Name must be 5 characters or greater."); } else { validateReturnType = new Success("Name is valid."); } return validateReturnType; } Are there any pitfalls with unit testing the return type of an function? Also, is it considered bad design to have functions needing to be run in order for them to succeed? In this example, Validate() would have to be run before IsValid() or else IsValid() would always return false. Thank you.

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  • R optimization: How can I avoid a for loop in this situation?

    - by chrisamiller
    I'm trying to do a simple genomic track intersection in R, and running into major performance problems, probably related to my use of for loops. In this situation, I have pre-defined windows at intervals of 100bp and I'm trying to calculate how much of each window is covered by the annotations in mylist. Graphically, it looks something like this: 0 100 200 300 400 500 600 windows: |-----|-----|-----|-----|-----|-----| mylist: |-| |-----------| So I wrote some code to do just that, but it's fairly slow and has become a bottleneck in my code: ##window for each 100-bp segment windows <- numeric(6) ##second track mylist = vector("list") mylist[[1]] = c(1,20) mylist[[2]] = c(120,320) ##do the intersection for(i in 1:length(mylist)){ st <- floor(mylist[[i]][1]/100)+1 sp <- floor(mylist[[i]][2]/100)+1 for(j in st:sp){ b <- max((j-1)*100, mylist[[i]][1]) e <- min(j*100, mylist[[i]][2]) windows[j] <- windows[j] + e - b + 1 } } print(windows) [1] 20 81 101 21 0 0 Naturally, this is being used on data sets that are much larger than the example I provide here. Through some profiling, I can see that the bottleneck is in the for loops, but my clumsy attempt to vectorize it using *apply functions resulted in code that runs an order of magnitude more slowly. I suppose I could write something in C, but I'd like to avoid that if possible. Can anyone suggest another approach that will speed this calculation up?

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  • How can I avoid encoding mixups of strings in a C/C++ API?

    - by Frerich Raabe
    I'm working on implementing different APIs in C and C++ and wondered what techniques are available for avoiding that clients get the encoding wrong when receiving strings from the framework or passing them back. For instance, imagine a simple plugin API in C++ which customers can implement to influence translations. It might feature a function like this: const char *getTranslatedWord( const char *englishWord ); Now, let's say that I'd like to enforce that all strings are passed as UTF-8. Of course I'd document this requirement, but I'd like the compiler to enforce the right encoding, maybe by using dedicated types. For instance, something like this: class Word { public: static Word fromUtf8( const char *data ) { return Word( data ); } const char *toUtf8() { return m_data; } private: Word( const char *data ) : m_data( data ) { } const char *m_data; }; I could now use this specialized type in the API: Word getTranslatedWord( const Word &englishWord ); Unfortunately, it's easy to make this very inefficient. The Word class lacks proper copy constructors, assignment operators etc.. and I'd like to avoid unnecessary copying of data as much as possible. Also, I see the danger that Word gets extended with more and more utility functions (like length or fromLatin1 or substr etc.) and I'd rather not write Yet Another String Class. I just want a little container which avoids accidental encoding mixups. I wonder whether anybody else has some experience with this and can share some useful techniques. EDIT: In my particular case, the API is used on Windows and Linux using MSVC 6 - MSVC 10 on Windows and gcc 3 & 4 on Linux.

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  • What are the interets of synthetic methods?

    - by romaintaz
    Problem One friend suggested an interesting problem. Given the following code: public class OuterClass { private String message = "Hello World"; private class InnerClass { private String getMessage() { return message; } } } From an external class, how may I print the message variable content? Of course, changing the accessibility of methods or fields is not allowed. (the source here, but it is a french blog) Solution The code to solve this problem is the following: try { Method m = OuterClass.class.getDeclaredMethod("access$000", OuterClass.class); OuterClass outerClass = new OuterClass(); System.out.println(m.invoke(outerClass, outerClass)); } catch (Exception e) { e.printStackTrace(); } Note that the access$000 method name is not really standard (even if this format is the one that is strongly recommanded), and some JVM will name this method access$0. Thus, a better solution is to check for synthetic methods: Method method = null; int i = 0; while ((method == null) && (i < OuterClass.class.getDeclaredMethods().length)) { if (OuterClass.class.getDeclaredMethods()[i].isSynthetic()) { method = OuterClass.class.getDeclaredMethods()[i]; } i++; } if (method != null) { try { System.out.println(method.invoke(null, new OuterClass())); } catch (Exception e) { e.printStackTrace(); } } So the interesting point in this problem is to highlight the use of synthetic methods. With these methods, I can access a private field as it was done in the solution. Of course, I need to use reflection, and I think that the use of this kind of thing can be quite dangerous... Question What is the interest - for me, as a developer - of a synthetic method? What can be a good situation where using the synthetic can be useful?

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  • Scheme Function to reverse elements of list of 2-list

    - by sudhirc
    This is an exercise from EOPL. Procedure (invert lst) takes lst which is a list of 2-lists and returns a list with each 2-list reversed. (define invert (lambda (lst) (cond((null? lst ) '()) ((= 2 (rtn-len (car lst))) ( cons(swap-elem (car lst)) (invert (cdr lst)))) ("List is not a 2-List")))) ;; Auxiliry Procedure swap-elements of 2 element list (define swap-elem (lambda (lst) (cons (car (cdr lst)) (car lst)))) ;; returns lengh of the list by calling (define rtn-len (lambda (lst) (calc-len lst 0))) ;; calculate length of the list (define calc-len (lambda (lst n) (if (null? lst) n (calc-len (cdr lst) (+ n 1))))) This seems to work however looks very verbose. Can this be shortened or written in more elegant way ? How I can halt the processing in any of the individual element is not a 2-list? At the moment execution proceed to next member and replacing current member with "List is not a 2-List" if current member is not a 2-list.

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  • Unexpected behaviour of Process.MainWindowHandle

    - by Ed Guiness
    I've been trying to understand Process.MainWindowHandle. According to MSDN; "The main window is the window that is created when the process is started. After initialization, other windows may be opened, including the Modal and TopLevel windows, but the first window associated with the process remains the main window." (Emphasis added) But while debugging I noticed that MainWindowHandle seemed to change value... which I wasn't expecting, especially after consulting the documentation above. To confirm the behaviour I created a standalone WinForms app with a timer to check the MainWindowHandle of the "DEVENV" (Visual Studio) process every 100ms. Here's the interesting part of this test app... IntPtr oldHWnd = IntPtr.Zero; void GetMainwindowHandle() { Process[] processes = Process.GetProcessesByName("DEVENV"); if (processes.Length!=1) return; IntPtr newHWnd = processes[0].MainWindowHandle; if (newHWnd != oldHWnd) { oldHWnd = newHWnd; textBox1.AppendText(processes[0].MainWindowHandle.ToString("X")+"\r\n"); } } private void timer1Tick(object sender, EventArgs e) { GetMainwindowHandle(); } You can see the value of MainWindowHandle changing when you (for example) click on a drop-down menu inside VS. Perhaps I've misunderstood the documentation. Can anyone shed light?

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  • What new Unicode functions are there in C++0x?

    - by luiscubal
    It has been mentioned in several sources that C++0x will include better language-level support for Unicode(including types and literals). If the language is going to add these new features, it's only natural to assume that the standard library will as well. However, I am currently unable to find any references to the new standard library. I expected to find out the answer for these answers: Does the new library provide standard methods to convert UTF-8 to UTF-16, etc.? Does the new library allowing writing UTF-8 to files, to the console (or from files, from the console). If so, can we use cout or will we need something else? Does the new library include "basic" functionality such as: discovering the byte count and length of a UTF-8 string, converting to upper-case/lower-case(does this consider the influence of locales?) Finally, are any of these functions are available in any popular compilers such as GCC or Visual Studio? I have tried to look for information, but I can't seem to find anything? I am actually starting to think that maybe these things aren't even decided yet(I am aware that C++0x is a work in progress).

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  • Trouble swapping values as keys in generic java BST class

    - by user1729869
    I was given a generic binary search tree class with the following declaration: public class BST<K extends Comparable<K>, V> I was asked to write a method that reverses the BST such that the values become the keys and keys become values. When I call the following method (defined in the class given) reverseDict.put(originalDict.get(key), key); I get the following two error messages from Netbeans: Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - Erroneous sym type: BST.put And also: no suitable method found for put(V,K) method BST.put(BST<K,V>.Node,K,V) is not applicable (actual and formal argument lists differ in length) method BST.put(K,V) is not applicable (actual argument V cannot be converted to K by method invocation conversion) where V,K are type-variables: V extends Object declared in method <K,V>reverseBST(BST<K,V>) K extends Comparable<K> declared in method <K,V>reverseBST(BST<K,V>) From what the error messages are telling me, since my values do not extend Comparable I am unable to use them as keys. If I am right, how can I get around that without changing the class given (maybe a cast)?

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  • Very simple code for number search gives me infinite loop

    - by Joshua
    Hello, I am a newbie Computer Science high school student and I have trouble with a small snippet of code. Basically, my code should perform a basic CLI search in an array of integers. However, what happens is I get what appears to be an infinite loop (BlueJ, the compiler I'm using, gets stuck and I have to reset the machine). I have set break points but I still don't quite get the problem...(I don't even understand most of the things that it tells me) Here's the offending code (assume that "ArrayUtil" works, because it does): import java.util.Scanner; public class intSearch { public static void main(String[] args) { search(); } public static void search() { int[] randomArray = ArrayUtil.randomIntArray(20, 100); Scanner searchInput = new Scanner(System.in); int searchInt = searchInput.nextInt(); if (findNumber(randomArray, searchInt) == -1) { System.out.println("Error"); }else System.out.println("Searched Number: " + findNumber(randomArray, searchInt)); } private static int findNumber(int[] searchedArray, int searchTerm) { for (int i = 0; searchedArray[i] == searchTerm && i < searchedArray.length; i++) { return i; } return -1; } } This has been bugging me for some time now...please help me identify the problem!

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  • Intelligent Merge of two Arrays (3-way-kindof)

    - by simon.oberhammer
    I have to Arrays, each represents a list of Stories. Two users can concurrently modify the order, add or remove Stories, and I want those changes merged. An example should make this clearer Orignial 1,2,3,4,5 UserA (mine) 3,1,2,4,5 (moved story 3 to start) UserB (theirs) 1,2,3,5,4 (moved story 5 forward) The result of the above should be Merge (result) 3,1,2,5,4 In case of conflicts, UserA should always win. I came pretty far with this simple approach. First i deleted whatever mine says i should deleted (that part of the code is not shown, it's trivial), then I iterate of mine, inserting and moving from theirs what is needed (mstories = mine, tstories = theirs): var offset = 0; for (var idx=0;idx<mstories.length;idx++) { var storyId = mstories[idx]; // new story in theirs if (mstories.indexOf(tstories[idx]) == -1) { mstories.splice(idx+1, 0, tstories[idx]); idx--; continue; } // new story in mine? if (tstories.indexOf(storyId) == -1) { tstories.splice(idx+offset, 0, storyId); offset += 1; // story moved } else if (tstories.indexOf(storyId) != idx + offset) { tstories.splice(tstories.indexOf(storyId), 1); tstories.splice(idx+offset, 0, storyId); } } It's close, but it gets confused when too many Stories are moved to the front / back with Stories in between, which the other User touched. I have an extended version which does checks on the original and is smarter - holding 2 offsets, etc - , but I feel like this is a problem that must have a) a name b) a perfect solution and i don't want to re-invent it.

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  • How do you convert an unsigned int[16] of hexidecimal to an unsigned char array without losing any information?

    - by user1068636
    I have a unsigned int[16] array that when printed out looks like this: 4418703544ED3F688AC208F53343AA59 The code used to print it out is this: for (i = 0; i < 16; i++) printf("%X", CipherBlock[i] / 16), printf("%X",CipherBlock[i] % 16); printf("\n"); I need to pass this unsigned int array "CipherBlock" into a decrypt() method that only takes unsigned char *. How do correctly memcpy everything from the "CipherBlock" array into an unsigned char array without losing information? My understanding is an unsigned int is 4 bytes and unsigned char 1 byte. Since "CipherBlock" is 16 unsigned integers, the total size in bytes = 16 * 4 = 64 bytes. Does this mean my unsigned char[] array needs to be 64 in length? If so, would the following work? unsigned char arr[64] = { '\0' }; memcpy(arr,CipherBlock,64); This does not seem to work. For some reason it only copies the the first byte of "CipherBlock" into "arr". The rest of "arr" is '\0' thereafter.

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  • splice() not working on correctly

    - by adardesign
    I am setting a cookie for each navigation container that is clicked on. It sets an array that is joined and set the cookie value. if its clicked again then its removed from the array. It somehow buggy. It only splices after clicking on other elements. and then it behaves weird. It might be that splice is not the correct method Thanks much. var navLinkToOpen; var setNavCookie = function(value){ var isSet = false; var checkCookies = checkNavCookie() setCookieHelper = checkCookies? checkCookies.split(","): []; for(i in setCookieHelper){ if(value == setCookieHelper[i]){ setCookieHelper.splice(value,1); isSet = true; } } if(!isSet){setCookieHelper.push(value)} setCookieHelper.join(",") document.cookie = "navLinkToOpen"+"="+setCookieHelper; } var checkNavCookie = function(){ var allCookies = document.cookie.split( ';' ); for (i = 0; i < allCookies.length; i++ ){ temp = allCookies[i].split("=") if(temp[0].match("navLinkToOpen")){ var getValue = temp[1] } } return getValue || false } $(document).ready(function() { $("#LeftNav li").has("b").addClass("navHeader").not(":first").siblings("li").hide() $(".navHeader").click(function(){ $(this).toggleClass("collapsed").nextUntil("li:has('b')").slideToggle(300); setNavCookie($('.navHeader').index($(this))) return false }) var testCookies = checkNavCookie(); if(testCookies){ finalArrayValue = testCookies.split(",") for(i in finalArrayValue){ $(".navHeader").eq(finalArrayValue[i]).toggleClass("collapsed").nextUntil(".navHeader").slideToggle (0); } } });

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  • JQuyer slide and stop issues: animated element freezes with quick mouse movement

    - by sherlock
    Here is Zi JsFiddle. In order to replicate my issue you have to hover over the link that says 'javascript', then mouseout that, then mouseback in. If you do this before the animation is complete, the pink slidedown #subMenu will freeze midway through sliding. Is there a way to prevent this from happening? I have tried some .stop()s , but i really don't want the animation to re-start every time you mouseenter or leave the .navLink . The animation should begin from where it left off. In other words, if the pink section is halfway down, and a slideDown() gets executed, the pink should not dissappear and then slide down, it should slide down from where it is. Thanks!! JS: $('header#subHeader').hide(); $('.navLink').hover(function () { if ($(this).children('div').length > 0) { var subMenu = $(this).find('.subMenu').html(); $('header#subHeader').empty().append('<div>' + subMenu + '</div>').stop().slideDown(); } else { $('header#subHeader').stop().slideUp(); } }); $('hgroup:first').on('mouseleave', function(){ $('header#subHeader').slideUp(); });

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  • Jumping onto next string when the condition is met

    - by user98235
    This was a problem related to one of the past topcoder exam problems called HowEasy. Let's assume that we're given a sentence, for instance, "We a1re really awe~~~some" I just wanted to take get rid of every word in the sentence that doesn't contain alphabet characters, so in the above sentence, the desired output would be "We really" The below is the code I wrote (incomplete), and I don't know how to move on to the next string when the condition (the string contains a character that's not alphabet) is met. Could you suggest some revisions or methods that would allow me to do that? vect would be the vector of strings containing the desired output string param; cin>>param; stringstream ss(param); vector<string> vect; string c; while(ss >> c){ for(int i=0; i < c.length(); i++){ if(!(97<=int(c[i])&&int(c[i])<=122) && !(65<=int(c[i])&&int(c[i])<=90)){ //I want to jump onto next string once the above condition is met //and ignore string c; } vect.push_back(c); if (ss.peek() == ' '){ ss.ignore(); } } }

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  • google maps in jquery mobile

    - by paullb
    When showing a google map in jquery mobile it appears (after reading the forums) that code like the following is required: <div data-role="page" data-theme="b" class="page-map" style="width:100%; height:100%;"> <div data-role="header"><h1>Map Page</h1></div> <div data-role="content" style="width:100%; height:100%; padding:0;"> <div id="map_canvas" style="width:100%; height:100%;"></div> </div> </div> Taking away the height on outside div causes the div to drop to height 0 and the map not being displayed. I was hoping to get some dynamic text below the map (based on the contents on the) which length I do not know so I can't set an absolute height. Has anyone got a workaround for this problem?

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  • How to update a string property of an sqlite database item

    - by Thomas Joos
    hi all, I'm trying to write an application that checks if there is an active internet connection. If so it reads an xml and checks every 'lastupdated' item ( php generated string ). It compares it to the database items and if there is a new value, this particular item needs to be updated. My code seems to work ( compiles, no error messages, no failures, .. ) but I notice that the particular property does not change, it becomese (null). When I output the binded string value it returns the correct string value I want to update into the db.. Any idea what I'm doing wrong? const char *sql = "update myTable Set last_updated=? Where node_id =?"; sqlite3_stmt *statement; // Preparing a statement compiles the SQL query into a byte-code program in the SQLite library. // The third parameter is either the length of the SQL string or -1 to read up to the first null terminator. if (sqlite3_prepare_v2(database, sql, -1, &statement, NULL) == SQLITE_OK){ NSLog(@"last updated item: %@", [d lastupdated]); sqlite3_bind_text(statement, 1, [d lastupdated],-1,SQLITE_TRANSIENT); sqlite3_bind_int (statement, 2, [d node_id]); }else { NSLog(@"SQLite statement error!"); } if(SQLITE_DONE != sqlite3_step(statement)){ NSAssert1(0, @"Error while updating. '%s'", sqlite3_errmsg(database)); }else { NSLog(@"SQLite Update done!"); }

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  • Visutal Studio Warning "Content is not allowed" in ASP.NET project

    - by pstar
    Hi, I am just started working as a programmer last month, so there will be plenty of newbie question come from me, stay tuned... I am now working on modify the provided template (from DevExpress) to create new web form using ASP.NET 2.0 on Visual Studio 2008. While the functionality of that web form is there, I am in the process of get rid of ninety something warning message, most of them come from the provided template. One of them puzzled me for a while is this one: "Warning 75 Content is not allowed between the opening and closing tags for element 'ClientSideEvents'." And here is the code: <dxe:ASPxListBox id="edtMultiResource" runat="server" width="100%" SelectionMode="CheckColumn" DataSource='<%# ResourceDataSource %>' Border-BorderWidth="0"> <ClientSideEvents SelectedIndexChanged="function(s, e) { var resourceNames = new Array(); var items = s.GetSelectedItems(); var count = items.length; if (count > 0) { for(var i=0; i<count; i++) _aspxArrayPush(resourceNames, items[i].text); } else _aspxArrayPush(resourceNames, ddResource.cp_Caption_ResourceNone); ddResource.SetValue(resourceNames.join(', ')); }"></ClientSideEvents> </dxe:ASPxListBox> I couldn't see anything wrong with the code myself, so please help me out here.

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  • In Excel 2010, how can I show a count of occurrences on a specific date within multiple time ranges?

    - by Justin
    Here's what I'm trying to do. I have three columns of data. ID, Date(MM/DD/YY), Time(00:00). I need to create a chart or table that shows the number of occurrences on, say, 12/10/2010 between 00:00 and 00:59, 1:00 and 1:59, etc, for each hour of the day. I can do countif and get results for the date, but I cannot figure out how to show a summary of the count of occurrences per hour for the 24 hour period. I have months of data and many times each day. Example of data set is below. Any help is greatly ID Date Time 221 12/10/2010 00:01 223 12/10/2010 00:45 227 12/10/2010 01:13 334 12/11/2010 14:45 I would like the results to read: Date Time Count 12/10/2010 00:00AM - 00:59AM 2 12/10/2010 01:00AM - 01:59AM 1 12/10/2010 02:00AM - 02:59AM 0 ......(continues for every hour of the day) 12/11/2010 00:00AM - 00:59AM 0 ......... 12/11/2010 14:00PM - 14:59PM 1 And so on. Sorry for the length but I wanted to be clear. EDIT Here is a sample spreadsheet. Very little data, but I couldn't figure out a better way without having a huge file. Tested in notepad for formatting and worked ok on import as csv. PID,Date,Time 2888759,12/10/2010,0:10 2888760,12/10/2010,0:10 2888761,12/10/2010,0:10 2888762,12/10/2010,0:11 2889078,12/10/2010,15:45 2889079,12/10/2010,15:57 2889080,12/10/2010,15:57 2889081,12/10/2010,15:58 2889082,12/10/2010,16:10 2889083,12/10/2010,16:11 2889084,12/10/2010,16:11 2889085,12/10/2010,16:12 2889086,12/10/2010,16:12 2889087,12/10/2010,16:12 2889088,12/10/2010,16:13 2891529,12/14/2010,16:21

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  • Using list() to extract a data.table inside of a function

    - by Nathan VanHoudnos
    I must admit that the data.table J syntax confuses me. I am attempting to use list() to extract a subset of a data.table as a data.table object as described in Section 1.4 of the data.table FAQ, but I can't get this behavior to work inside of a function. An example: require(data.table) ## Setup some test data set.seed(1) test.data <- data.table( X = rnorm(10), Y = rnorm(10), Z = rnorm(10) ) setkey(test.data, X) ## Notice that I can subset the data table easily with literal names test.data[, list(X,Y)] ## X Y ## 1: -0.8356286 -0.62124058 ## 2: -0.8204684 -0.04493361 ## 3: -0.6264538 1.51178117 ## 4: -0.3053884 0.59390132 ## 5: 0.1836433 0.38984324 ## 6: 0.3295078 1.12493092 ## 7: 0.4874291 -0.01619026 ## 8: 0.5757814 0.82122120 ## 9: 0.7383247 0.94383621 ## 10: 1.5952808 -2.21469989 I can even write a function that will return a column of the data.table as a vector when passed the name of a column as a character vector: get.a.vector <- function( my.dt, my.column ) { ## Step 1: Convert my.column to an expression column.exp <- parse(text=my.column) ## Step 2: Return the vector return( my.dt[, eval(column.exp)] ) } get.a.vector( test.data, 'X') ## [1] -0.8356286 -0.8204684 -0.6264538 -0.3053884 0.1836433 0.3295078 ## [7] 0.4874291 0.5757814 0.7383247 1.5952808 But I cannot pull a similar trick for list(). The inline comments are the output from the interactive browser() session. get.a.dt <- function( my.dt, my.column ) { ## Step 1: Convert my.column to an expression column.exp <- parse(text=my.column) ## Step 2: Enter the browser to play around browser() ## Step 3: Verity that a literal X works: my.dt[, list(X)] ## << not shown >> ## Step 4: Attempt to evaluate the parsed experssion my.dt[, list( eval(column.exp)] ## Error in `rownames<-`(`*tmp*`, value = paste(format(rn, right = TRUE), (from data.table.example.R@1032mCJ#7) : ## length of 'dimnames' [1] not equal to array extent return( my.dt[, list(eval(column.exp))] ) } get.a.dt( test.data, "X" ) What am I missing? Update: Due to some confusion as to why I would want to do this I wanted to clarify. My use case is when I need to access a data.table column when when I generate the name. Something like this: set.seed(2) test.data[, X.1 := rnorm(10)] which.column <- 'X' new.column <- paste(which.column, '.1', sep="") get.a.dt( test.data, new.column ) Hopefully that helps.

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  • Best way to do one-to-many "JOIN" in CouchDB

    - by mit
    There are CouchDB documents that are list elements: { "type" : "el", "id" : "1", "content" : "first" } { "type" : "el", "id" : "2", "content" : "second" } { "type" : "el", "id" : "3", "content" : "third" } There is one document that defines the list: { "type" : "list", "elements" : ["2","1"] , "id" : "abc123" } As you can see the third element was deleted, it is no longer part of the list. So it must not be part of the result. Now I want a view that returns the content elements including the right order. The result could be: { "content" : ["second", "first"] } In this case the order of the elements is already as it should be. Another possible result: { "content" : [{"content" : "first", "order" : 2},{"content" : "second", "order" : 1}] } I started writing the map function: map = function (doc) { if (doc.type === 'el') { emit(doc.id, {"content" : doc.content}); //emit the id and the content exit; } if (doc.type === 'list') { for ( var i=0, l=doc.elements.length; i<l; ++i ){ emit(doc.elements[i], { "order" : i }); //emit the id and the order } } } This is as far as I can get. Can you correct my mistakes and write a reduce function? Remember that the third document must not be part of the result. Of course you can write a different map function also. But the structure of the documents (one definig element document and an entry document for each entry) cannot be changed.

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  • Optimizing a "set in a string list" to a "set as a matrix" operation

    - by Eric Fournier
    I have a set of strings which contain space-separated elements. I want to build a matrix which will tell me which elements were part of which strings. For example: "" "A B C" "D" "B D" Should give something like: A B C D 1 2 1 1 1 3 1 4 1 1 Now I've got a solution, but it runs slow as molasse, and I've run out of ideas on how to make it faster: reverseIn <- function(vector, value) { return(value %in% vector) } buildCategoryMatrix <- function(valueVector) { allClasses <- c() for(classVec in unique(valueVector)) { allClasses <- unique(c(allClasses, strsplit(classVec, " ", fixed=TRUE)[[1]])) } resMatrix <- matrix(ncol=0, nrow=length(valueVector)) splitValues <- strsplit(valueVector, " ", fixed=TRUE) for(cat in allClasses) { if(cat=="") { catIsPart <- (valueVector == "") } else { catIsPart <- sapply(splitValues, reverseIn, cat) } resMatrix <- cbind(resMatrix, catIsPart) } colnames(resMatrix) <- allClasses return(resMatrix) } Profiling the function gives me this: $by.self self.time self.pct total.time total.pct "match" 31.20 34.74 31.24 34.79 "FUN" 30.26 33.70 74.30 82.74 "lapply" 13.56 15.10 87.86 97.84 "%in%" 12.92 14.39 44.10 49.11 So my actual questions would be: - Where are the 33% spent in "FUN" coming from? - Would there be any way to speed up the %in% call? I tried turning the strings into factors prior to going into the loop so that I'd be matching numbers instead of strings, but that actually makes R crash. I've also tried going for partial matrix assignment (IE, resMatrix[i,x] <- 1) where i is the number of the string and x is the vector of factors. No dice there either, as it seems to keep on running infinitely.

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  • JQuery modal box form validation

    - by vikitor
    Hi, I was using a view to create an object for my specific project, but now I have to adapt this to another requirements, such as the creation of this object must be integrated in the creation of another one. The thing is, that this object must be created before starting to create the other one, and the way of doing it will be poping up a modal dialog box with JQuery with the form to create it. I've got to adapt the creation and it works fine, except for the validation messages. It is made in the controller like : if (not.NotName.Trim().Length == 0) { ModelState.AddModelError("NotName", "Name is required"); } if (_notification.checkIfExists(not.NotName, not.NotRecID)) { ModelState.AddModelError("NotName", "Notification already exists"); } And before with a normal view it worked fine, but now I'm not able to get the validation messages as I did. How can you get this validation messages thrown by the controller in the Modal Box? Because now when I made a mistake on purpose in the form in order to get the error it doesn't appear. I've seen the error is displayed in the site, because I've seen it on firebug, but it doesn't appear in my model box. How can I retrieve this errors? Do you know any tutorial that could help me with this? Thank you

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  • C# textbox cursor positioning

    - by Jim
    I feel like I am just missing a simple property, but can you set the cursor to the end of a line in a textbox? private void txtNumbersOnly_KeyPress(object sender, KeyPressEventArgs e) { if (Char.IsDigit(e.KeyChar) || e.KeyChar == '\b' || e.KeyChar == '.' || e.KeyChar == '-') { TextBox t = (TextBox)sender; bool bHandled = false; _sCurrentTemp += e.KeyChar; if (_sCurrentTemp.Length > 0 && e.KeyChar == '-') { // '-' only allowed as first char bHandled = true; } if (_sCurrentTemp.StartsWith(Convert.ToString('.'))) { // add '0' in front of decimal point t.Text = string.Empty; t.Text = '0' + _sCurrentTemp; _sCurrentTemp = t.Text; bHandled = true; } e.Handled = bHandled; } After testing for '.' as first char, the cursor goes before the text that is added. So instead of "0.123", the results are "1230." without moving the cursor myself. I also apologize if this is a duplicate question.

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  • Better way to download a binary file?

    - by geoff
    I have a site where a user can download a file. Some files are extremely large (the largest being 323 MB). When I test it to try and download this file I get an out of memory exception. The only way I know to download the file is below. The reason I'm using the code below is because the URL is encoded and I can't let the user link directly to the file. Is there another way to download this file without having to read the whole thing into a byte array? FileStream fs = new FileStream(context.Server.MapPath(url), FileMode.Open, FileAccess.Read); BinaryReader br = new BinaryReader(fs); long numBytes = new FileInfo(context.Server.MapPath(url)).Length; byte[] bytes = br.ReadBytes((int) numBytes); string filename = Path.GetFileName(url); context.Response.Buffer = true; context.Response.Charset = ""; context.Response.Cache.SetCacheability(HttpCacheability.NoCache); context.Response.ContentType = "application/x-rar-compressed"; context.Response.AddHeader("content-disposition", "attachment;filename=" + filename); context.Response.BinaryWrite(bytes); context.Response.Flush(); context.Response.End();

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