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  • Ruby on Rails How do I access variables of a model inside itself like in this example?

    - by banditKing
    I have a Model like so: # == Schema Information # # Table name: s3_files # # id :integer not null, primary key # owner :string(255) # notes :text # created_at :datetime not null # updated_at :datetime not null # last_accessed_by_user :string(255) # last_accessed_time_stamp :datetime # upload_file_name :string(255) # upload_content_type :string(255) # upload_file_size :integer # upload_updated_at :datetime # class S3File < ActiveRecord::Base #PaperClip methods attr_accessible :upload attr_accessor :owner Paperclip.interpolates :prefix do |attachment, style| I WOULD LIKE TO ACCESS VARIABLE= owner HERE- HOW TO DO THAT? end has_attached_file( :upload, :path => ":prefix/:basename.:extension", :storage => :s3, :s3_credentials => {:access_key_id => "ZXXX", :secret_access_key => "XXX"}, :bucket => "XXX" ) #Used to connect to users through the join table has_many :user_resource_relationships has_many :users, :through => :user_resource_relationships end Im setting this variable in the controller like so: # POST /s3_files # POST /s3_files.json def create @s3_file = S3File.new(params[:s3_file]) @s3_file.owner = current_user.email respond_to do |format| if @s3_file.save format.html { redirect_to @s3_file, notice: 'S3 file was successfully created.' } format.json { render json: @s3_file, status: :created, location: @s3_file } else format.html { render action: "new" } format.json { render json: @s3_file.errors, status: :unprocessable_entity } end end end Thanks, any help would be appreciated.

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  • "for" loop from program 7.6 from Kochan's "Programming in Objective-C"

    - by Mr_Vlasov
    "The sigma notation is shorthand for a summation. Its use here means to add the values of 1/2^i, where i varies from 1 to n. That is, add 1/2 + 1/4 + 1/8 .... If you make the value of n large enough, the sum of this series should approach 1. Let’s experiment with different values for n to see how close we get." #import "Fraction.h" int main (int argc, char *argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; Fraction *aFraction = [[Fraction alloc] init]; Fraction *sum = [[Fraction alloc] init], *sum2; int i, n, pow2; [sum setTo: 0 over: 1]; // set 1st fraction to 0 NSLog (@"Enter your value for n:"); scanf ("%i", &n); pow2 = 2; for (i = 1; i <= n; ++i) { [aFraction setTo: 1 over: pow2]; sum2 = [sum add: aFraction]; [sum release]; // release previous sum sum = sum2; pow2 *= 2; } NSLog (@"After %i iterations, the sum is %g", n, [sum convertToNum]); [aFraction release]; [sum release]; [pool drain]; return 0; } Question: Why do we have to create additional variable sum2 that we are using in the "for" loop? Why do we need "release previous sum" here and then again give it a value that we just released? : sum2 = [sum add: aFraction]; [sum release]; // release previous sum sum = sum2; Is it just for the sake of avoiding memory leakage? (method "add" initializes a variable that is stored in sum2)

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  • Android: How to declare global variables?

    - by niko
    Hi, I am creating an application which requires login. I created the main and the login activity. In the main activity onCreate method I added the following condition: public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); ... loadSettings(); if(strSessionString == null) { login(); } ... } The onActivityResult method which is executed when the login form terminates looks like this: @Override public void onActivityResult(int requestCode, int resultCode, Intent data) { super.onActivityResult(requestCode, resultCode, data); switch(requestCode) { case(SHOW_SUBACTICITY_LOGIN): { if(resultCode == Activity.RESULT_OK) { strSessionString = data.getStringExtra(Login.SESSIONSTRING); connectionAvailable = true; strUsername = data.getStringExtra(Login.USERNAME); } } } The problem is the login form sometimes appears twice (the login() method is called twice) and also when the phone keyboard slides the login form appears again and I guess the problem is the variable strSessionString. Does anyone know how to set the variable global in order to avoid login form appearing after the user already successfully authenticates? Thanks!

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  • how are association, aggregation and composition written?

    - by ajsie
    i have read some posts about the differences between these 3 relationships and i think i get the point. i just wonder, are all these written the same when coding? question 1: all 3 are just a value of the object type in a instance variable? class A { public $b = '' public function __construct($object) { $this->b = $object // <-- could be a association, aggregation or a composition relation? } } question 2: does it have to be an instance variable or can it be a static one? class A { public static $b = '' // <-- nothing changed? public function __construct($object) { $this->b = $object } } question 3: is there a difference in where the object is created? i tend to think that composition object is created inside the object: class A { public $b = '' public function __construct() { $this->b = new Object // is created inside the object } } and aggregation/association is passed through a constructor or another method: class A { public $b = '' public function __construct($object) { // passed through a method $this->b = $object } } question 4: why/when is this important to know. do i have to comment an object inside another what relation its about or do you do it in an UML diagram? could someone shed a light on these questions. thanks!

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  • How do I slow down a flash game?

    - by dsaccount1
    Basically the objective is to click on certain targets, which upon doing so would destroy the target and garner you points. I've written a macro to help me until the point where its impossible to even see the target more than a mere flicker, (maybe even less than that, i cant see it with my eyes). But its possible because i believe others have done so. (Maybe on slower comps?) Anyway the question is, how would it be possible to slow down the flash game? I've thought of a couple of ways that could work but i'm not sure how to implement them. 1. Slow down the cpu speed? (smth like that? how?) 2. As the game progress the time the targets appear and stay up is reduced. Maybe theres a variable controlling all of this, isit possible to modify the address of this variable? freeze it or smth? Any ideas, suggestions and especially advice would really be appreciated, thanks!

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  • Else statement crashes when i enter a letter for a cin << int value

    - by TimothyTech
    Alright, i have a question, i veered away from using strings for selection so now i use an integer.when the user enters a number then the game progresses. if they enter a wrong character it SHOULD give the else statement, however if i enter a letter or character the system goes into an endless loop effect then crashes. is there a way to give the else statement even if the user defies the variable's type. // action variable; int c_action: if (c_action == 1){ // enemy attack and user attack with added effect buffer. /////////////////////////////////////////////////////// u_attack = userAttack(userAtk, weapons); enemyHP = enemyHP - u_attack; cout << " charging at the enemy you do " << u_attack << "damage" << endl; e_attack = enemyAttack(enemyAtk); userHP = userHP - e_attack; cout << "however he lashes back causing you to have " << userHP << "health left " << endl << endl << endl << endl; //end of ATTACK ACTION }else{ cout << "invalid actions" << endl; goto ACTIONS; }

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  • decoding jquery json data in php

    - by Mac Taylor
    hey guys recenlty i made a script to move objects and save the orders now i have a little to do to finish this script everything works fine , just one question : how can i save not numeric data in my json script this is my script : function updateWidgetData(){ var items=[]; $('.widget-title').each(function(){ var weightId=$(this).attr('id'); $('.column').each(function(){ var columnId=$(this).attr('id'); $('.widget', this).each(function(i){ var collapsed=0; if($(this).find('.widget-inside').css('display')=="none") collapsed=1; //Create Item object for current panel var item={ id: $(this).attr('id'), collapsed: collapsed, order : i, column: columnId, weight: weightId }; //Push item object into items array items.push(item); }); }); }); //Assign items array to sortorder JSON variable var sortorder={ items: items }; //Pass sortorder variable to server using ajax to save state $.post('updatePanels.php', 'data='+$.toJSON(sortorder), function(response){ if(response=="success") $("#console").html('<div class="success">Saved</div>').hide().fadeIn(1000); setTimeout(function(){ $('#console').fadeOut(1000); }, 2000); }); } and this is my php script : $data=json_decode($_POST["data"]); foreach($data->items as $item) { //Extract column number for panel $col_id=preg_replace('/[^\d\s]/', '', $item->column); //Extract id of the panel $widget_id=preg_replace('/[^\d\s]/', '', $item->id); $sql="UPDATE widgets SET column_id='$col_id', sort_no='".$item->order."', collapsed='".$item->collapsed."' WHERE id='".$widget_id."'"; mysql_query($sql) or die('Error updating widget DB'); } echo "success"; everything works fine till i use numeric value for columns' id but i need non numeric values forexample id='columnr' i want to extract r but i cant get it right any help plz !?

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  • Adding International support in Erlang Web 1.4

    - by Roberto Aloi
    I'm trying to add international support for a website based on the Erlang Web 1.4. I would like to have a couple of links on every page (the notorious Country flags) that allow the user to set his language session variable. What I have right now is a link like: <li><a href="/session/language/en">English</a></li> Where, in the session controller I do: language(Args) -> LanguageId = proplists:get_value(id, Args), case language_is_supported(LanguageId) of false -> ok; true -> wpart:fset("session:lang", LanguageId) end, {redirect, "/"}. The problem is that, after setting the preferred language, I would like the user to be redirected to the page he was visiting before changing the language. In this case the "__path" variable doesn't help because it contains the language request and not the "previous" one. How could I resolve this situation? I'm probably using the wrong approach but I cannot thing to anything else right now.

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  • Prolog Beginner: How to unify with arithmentic cmparison operators or how to get a set var to range

    - by sixtyfootersdude
    I am new to prolog. I need to write an integer adder that will add numbers between 0-9 to other numbers 0-9 and produce a solution 0-18. This is what I want to do: add(in1, in2, out) :- in1 < 10, in2 < 10, out < 18. I would like to be able to call it like this: To Check if it is a valid addition: ?- add(1,2,3). true ?- add(1,2,4). false With one missing variable: ?- add(X,2,3). 1 ?- add(1,4,X). 5 With multiple missing variables: ?-add(X,Y,Z). % Some output that would make sense. Some examples could be: X=1, Y=1, Z=2 ; X=2, Y=1, Z=3 ...... I realize that this is probably a pretty simplistic question and it is probably very straightforward. However cording to the prolog tutorial I am using: "Unlike unification Arithmetic Comparison Operators operators cannot be used to give values to a variable. The can only be evaluated when every term on each side have been instantiated."

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  • Data conversion from accelerometer

    - by mrigendra
    Hi all I am working on an accelerometer bma220 , and its datasheet says that data is in 2's complement form.So what i had to do was getting that 8 bit data in any 8 bit signed char and done. the bma220 have an 8 bit register of which first 6 bits are data and last two are zero. void properdata(int16_t *msgData) { printf("\nin proper data\n"); int16_t temp, i; for(i=0; i<3; i++) { temp = *(msgData + i); printf("temp = %d sense = %d\n", temp, sense); temp = temp >> 2; // only 6 bits data temp = temp / sense; //decimal value * .0625 = value in g printf("temp = %d\n", temp); } } in this program i am taking data in a unsigned variable msgdata and doing all the calculations on a signed variable. I just need to know if this is the correct way to convert data?

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  • Using placeholders/variables in a sed command

    - by jesse_galley
    I want to store a specific part of a matched result as a variable to be used for replacement later. I would like to keep this in a one liner instead of finding the variable I need before hand. when configuring apache, and use mod_rewrite, you can specificy specific parts of patterns to be used as variables,like this: RewriteRule ^www.example.com/page/(.*)$ http://www.example.com/page.php?page=$1 [R=301,L] the part of the pattern match that's contained inside the parenthesis is stored as $1 for use later. So if the url was www.example.com/page/home, it would be replaced with www.example.com/page.php?page=home. So the "home" part of the match was saved in $1 because it was the part of the pattern inside the parenthesis. I want something like this functionality with a sed command, I need to automatically replace many strings in a SQL dump file, to add drop table if exist commands before each create table, but I need to know the table name to do this, so if the dump file contains something like: ... CREATE TABLE `orders` ... I need to run something like: cat dump.sql | sed "s/CREATE TABLE `(.*)`/DROP TABLE IF EXISTS $1\N CREATE TABLE `$1`/g" to get the result of: ... DROP TABLE IF EXISTS `orders` CREATE TABLE `orders` ... I'm using the mod_rewrite syntax in the sed command as a logical example of what I'm trying to do. Any suggestions?

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  • game currency convert: math efficient

    - by Comradsky
    For variables:4 text views named diamondText, goldText, silverText, and bronzeText;money variable unsigned int money;and an NSTimer, every .1 sec,runs function: -(void)updateMoney{ money++; bronzeText.text = [NSString stringWithFormat:@"%d",money]; silverText.text = [NSString stringWithFormat:@"%d",money%10]; goldText.text = [NSString stringWithFormat:@"%d",money%100]; diamondText.text= [NSString stringWithFormat:@"%d",money%1000]; } Given that my currency is diamond = 10 gold = 10 silver = 10 bronze = 1; What would be most efficient way to calculate and display the money labels? How would you store this variable, with GameCenter and NSDictionary or GameCenter and something else? More details are below if you don't understand. To clarify: bronze has the last 2 numbers, silver has the next 2 numbers, and so on. I understand I could use 4 ints or an array, but i would rather try to use this method, unless theres a much more efficient way. Example: When money = 1000;bronzeText = nothing, silverText = 10,goldText = nothing, diamondText = nothing; What other ways would you do this that you think would be more efficient? I will be calling a function (void)collisionDetector that detects if my player.frame crosses with a flyingObject.frame, and if that object is a coin it gives an added value to money and then calls (void)updateMoney. Im just using the timer to test this and spawn these flying objects.

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  • What is common between environments within a shell terminal session?

    - by Matt1776
    I have a custom shell script that runs each time a user logs in or identity is assumed, its been placed in /etc/profile.d and performs some basic env variable operations. Recently I added some code so that if screen is running it will reattach it without needing me to type anything. There are some problems however. If I log-in as root, and su - to another user, the code runs a second time. Is there a variable I can set when the code runs the first time that will prevent a second run of the code? I thought to write something to the disk but then I dont want to prevent the code from running if I begin a new terminal session. Here is the code in question. It first attempts to reattach - if unsuccessful because its already attached (as it might be on an interruped session) it will 'take' the session back. screen -r if [ -z "$STY" ]; then exec screen -dR fi Ultimately this bug prevents me from substituting user to another user because as soon as I do so, it grabs the screen session and puts me right back where I started. Pretty frustrating

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  • Problem with PHP localeconv() - Maybe UTF-8

    - by Chuck Ugwuh
    I'm having an issue with the localeconv() in PHP. I'm using a Windows PC. I set my locale to France using setLocale(LC_ALL, 'fra_fra') function. Then I call the localeconv() function to a variable. When I output that variable, below is what I get. Array ( [decimal_point] = , [thousands_sep] = ? [int_curr_symbol] = EUR [currency_symbol] = ? [mon_decimal_point] = , [mon_thousands_sep] = ? [positive_sign] = [negative_sign] = - [int_frac_digits] = 2 [frac_digits] = 2 [p_cs_precedes] = 0 [p_sep_by_space] = 1 [n_cs_precedes] = 0 [n_sep_by_space] = 1 [p_sign_posn] = 1 [n_sign_posn] = 1 [grouping] = Array ( [0] = 3 ) [mon_grouping] = Array ( [0] = 3 ) ) I'm not sure if it is a UTF-8 display issue. I've done the following: Set my default_charset in PHP.ini to UTF-8 The Content-type on my page is UTF-8 I've also called same in a header i.e. header('Content-type: text/html; charset=utf-8') I'm using firefox and changed the charset there too, still no luck I also updated my http.conf file with AddDefaultCharset, but still no cigar I'm completely stumped and not sure what next to do. Can anyone help out? Thanks.

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  • How to insert result of mysql_real_escape_string() into oracle database?

    - by Prat
    For inserting special characters in data like (,')etc., I am using musql_real_escape_string() function & it's working fine. Now I want to use same variable while inserting values in Oracle. $str = 'N.G.Palace\'s Building', 'xyzcity', '12345678','India','100001',12 Here $str is result of mysql_real_escape_string(). so it escapes special character. Now my code for oracle is like this-: $qry ="INSERT INTO Ora_table(ship_to_street, ship_to_city,ship_to_country, ship_to_telephone, order_id, record_no) VALUES(".$str); So my doubt is Oracle is not accepting values return by mysql_real_escape_string i.e. Palace\'s (like this as this mysql function attach \ before 'single quote)? So can anybody tell me ho9w can I use that variable $str to insert data into Oracle? Also I tried like this also-: "q"."'"."c".$str."c"."'" can we use this for multiple values like in my case...though still I am unable to inser data in oracle? plz help.

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  • Pickled my dictionary from ZODB but i got a less in size one?

    - by Someone Someoneelse
    I use ZODB and i want to copy my 'database_1.fs' file to another 'database_2.fs', so I opened the root dictionary of that 'database_1.fs' and I (pickle.dump) it in a text file. Then I (pickle.load) it in a dictionary-variable, in the end I update the root dictionary of the other 'database_2.fs' with the dictionary-variable. It works, but I wonder why the size of the 'database_1.fs' not equal to the size of the other 'database_2.fs'. They are still copies of each other. def openstorage(store): #opens the database data={} data['file']=filestorage data['db']=DB(data['file']) data['conn']=data['db'].open() data['root']=data['conn'].root() return data def getroot(dicty): return dicty['root'] def closestorage(dicty): #close the database after Saving transaction.commit() dicty['file'].close() dicty['db'].close() dicty['conn'].close() transaction.get().abort() then that's what i do:- import pickle loc1='G:\\database_1.fs' op1=openstorage(loc1) root1=getroot(op1) loc2='G:database_2.fs' op2=openstorage(loc2) root2=getroot(op2) >>> len(root1) 215 >>> len(root2) 0 pickle.dump( root1, open( "save.txt", "wb" )) item=pickle.load( open( "save.txt", "rb" ) ) #now item is a dictionary root2.update(item) closestorage(op1) closestorage(op2) #after I open both of the databases #I get the same keys in both databases #But `database_2.fs` is smaller that `database_2.fs` in size I mean. >>> len(root2)==len(root1)==215 #they have the same keys True Note: (1) there are persistent dictionaries and lists in the original database_1.fs (2) both of them have the same length and the same indexes.

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  • Android Notepadv1 Tutorial - Persistent mNoteNumber?

    - by Chris L.
    So I did the Notepadv1 tutorial. It worked great. No problems. I would however like some explanation on why the mNoteNumber remembers the last number of the item I created. So the class starts as follows: public class Notepadv1 extends ListActivity { private int mNoteNumber = 1; That's fine, I understand that. The only other time the mNoteNumber variable is used is when you add an item it creates a note with that number and then increments it to the next number as follows: private void createNote() { String noteName = "Note " + mNoteNumber++; Those are the only two references to the variable mNoteNumber. When I press the Home button and then reopen the app, I add a new note but instead of adding a second "Note 1" it remembers that the last note I added as "Note 3" so it makes "Note 4". So I don't get it. Does Java/Android remember the last state of variables? If anyone could give me some explanation that would be great THANKS!

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  • Best way to design a class in python

    - by Fraz
    So, this is more like a philosophical question for someone who is trying to understand classes. Most of time, how i use class is actually a very bad way to use it. I think of a lot of functions and after a time just indent the code and makes it a class and replacing few stuff with self.variable if a variable is repeated a lot. (I know its bad practise) But anyways... What i am asking is: class FooBar: def __init__(self,foo,bar): self._foo = foo self._bar = bar self.ans = self.__execute() def __execute(self): return something(self._foo, self._bar) Now there are many ways to do this: class FooBar: def __init__(self,foo): self._foo = foo def execute(self,bar): return something(self._foo, bar) Can you suggest which one is bad and which one is worse? or any other way to do this. This is just a toy example (offcourse). I mean, there is no need to have a class here if there is one function.. but lets say in __execute something() calls a whole set of other methods.. ?? Thanks

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  • Exclude notes based on attribute wildcard in XSL node selection

    - by C A
    Using cruisecontrol for continuous integration, I have some annoyances with Weblogic Ant tasks and how they think that server debug information are warnings rather than debug, so are shown in my build report emails. The XML output from cruise is similar to: <cruisecontrol> <build> <target name="compile-xxx"> <task name="xxx" /> </target> <target name="xxx.weblogic"> <task name="wldeploy"> <message priority="warn">Message which isn't really a warning"</message> </task> </target> </build> </cruisecontrol> In the cruisecontrol XSL template the current selection for the task list is: <xsl:variable name="tasklist" select="/cruisecontrol/build//target/task"/> What I would like is something which selects the tasklist in the same way, but doesn't include any target nodes which have the attribute name="*weblogic" where * is a wildcard. I have tried <xsl:variable name="tasklist" select="/cruisecontrol/build//target[@name!='*weblogic']/task"/> but this doesn't seem to have worked. I'm not an expert with XSLT, and just want to get this fixed so I can carry on the real development of the project. Any help is much appreciated.

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  • Exclude nodes based on attribute wildcard in XSL node selection

    - by C A
    Using cruisecontrol for continuous integration, I have some annoyances with Weblogic Ant tasks and how they think that server debug information are warnings rather than debug, so are shown in my build report emails. The XML output from cruise is similar to: <cruisecontrol> <build> <target name="compile-xxx"> <task name="xxx" /> </target> <target name="xxx.weblogic"> <task name="wldeploy"> <message priority="warn">Message which isn't really a warning"</message> </task> </target> </build> </cruisecontrol> In the cruisecontrol XSL template the current selection for the task list is: <xsl:variable name="tasklist" select="/cruisecontrol/build//target/task"/> What I would like is something which selects the tasklist in the same way, but doesn't include any target nodes which have the attribute name="*weblogic" where * is a wildcard. I have tried <xsl:variable name="tasklist" select="/cruisecontrol/build//target[@name!='*weblogic']/task"/> but this doesn't seem to have worked. I'm not an expert with XSLT, and just want to get this fixed so I can carry on the real development of the project. Any help is much appreciated.

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  • visual studio attaching to a process in debug mode

    - by user1612986
    i have a strange problem. the dll that i built (lets call it my.dll) in c++ visual studio 2010 uses a third party library (say tp.lib) which in turn calls a third party dll (say tp.dll). for debugging prupose i have in configurationProperties-debugging-command: Excel.exe and configurationProperties-debugging-commandArguments: "$(TargetPath)" in my computer i also set PATH variable to the directory where tp.dll resides now when i hit the F5 in visual studio excel opens up with my.dll and crashes giving me a "cannot open in dos mode" error. the reason this happens is tp.dll is not deployed when debug version of my.dll is deployed. when i open an instance of excel seperately and manually drop the debug version of my.dll then everything works fine and i can see all my functions that i wrote in my.dll the only issue is now i do not know how to debug becuase i do not know how to attach visual studio to the instance of excel i opened up seperately. my question is: 1 how can i attach visual studio to an already opened instance of Excel or 2 how can i hit F5 and still make Excel pick up the required tp.dll from the directory specified in the PATH variable before it starts to deploy my.dll. any of these two will allow my to step through the code for the purpose of debugging. thanks in advance.

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  • Problem in homemade function to merge objects

    - by Eric
    I'm trying to make a function that merges arrays. The reason is, I have a function that supposed to get the settings of an entity, and merge them with the global defaults. //So for example, let's say globalOptions is something like this var globalOptions={opt1:'foo',opt2:'something'}; //and this is entityOptions var entityOptions={opt1:'foofoo',opt2:null}; The only difference is it has objects in objects and objects in objects in objects, so what I made was a function that loops through all objects, thinking I would later, easily be able to loop through it all. Please ignore the array thing. That is defected, but unneeded. function loopObj(obj, call, where, objcall, array) { if ($.isArray(obj) || $.isPlainObject(obj)) { for (i in obj) { if ($.isArray(obj)) { if (array) { loopObj(obj[i], call, where[where.length] = i, true); if (objcall) { call(obj[i],where,true); } } else { loopObj(obj[i], call, where+'['+i+']', false); if (objcall) { call(obj[i],where,true); } } } else { if (array) { loopObj(obj[i], call, where[where.length] = parseInt(i), true); if (objcall) { call(obj[i],where,true); } } else { loopObj(obj[i], call, where+'[\''+i+'\']', false); if (objcall) { call(obj[i],where,true); } } } } } else { return call(obj,where); } } Then I made this program to convert it: function mergeObj(a,b) { temp.retd = new Object(); loopObj(a,function (c,d) { if (c) { eval(d.replace('%par%','temp.retd'))=c; } else { eval(d.replace('%par%','temp.retd'))=eval(d.replace('%par%','b')); } },'%par%', true); return temp.retd(); } I get the error: Uncaught ReferenceError: Invalid left-hand side in assignment (anonymous function)base.js:51 loopObjbase.js:40 loopObjbase.js:31 mergeObjbase.js:46 (anonymous function)base.js:72 I know what it means, the eval returns an anonomys variable (copy of the variable), so I can't set it, only get it.

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  • What rules govern the copying of variables in Javascript closures?

    - by int3
    I'd just like to check my understanding of variable copying in Javascript. From what I gather, variables are passed/assigned by reference unless you explicitly tell them to create a copy with the new operator. But I'm a little uncertain when it comes to using closures. Say I have the following code: var myArray = [1, 5, 10, 15, 20]; var fnlist = []; for (var i in myArray) { var data = myArray[i]; fnlist.push(function() { var x = data; console.log(x); }); } fnlist[2](); // returns 20 I gather that this is because fnlist[2] only looks up the value of data at the point where it is invoked. So I tried an alternative tack: var myArray = [1, 5, 10, 15, 20]; var fnlist = []; for (var i in myArray) { var data = myArray[i]; fnlist.push(function() { var x = data; return function() { console.log(x); } }()); } fnlist[2](); // returns 10 So now it returns the 'correct' value. Am I right to say that it works because a function resolves all variable references to their 'constant' values when it is invoked? Or is there a better way to explain it? Any explanations / links to explanations regarding this referencing / copying business would be appreciated as well. Thanks!

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  • Selecting the correct input field using jquery

    - by rshivers
    I'm trying to select the id's of dynamic input fields in my code. When clicking a button, the form will create a form field like this: <td><input type="text" id="field_a_1"></td> <td><input type="text" id="field_b_1"></td> <td><input type="text" id="field_c_1"></td> When I click on the button again I get this: <td><input type="text" id="field_a_2"></td> <td><input type="text" id="field_b_2"></td> <td><input type="text" id="field_c_2"></td> What I want to do is select only the field id that I need to pull the value from that particular input and pass it to a variable like this: var example = $(":input:eq(0)").val(); I know that by adding the :eq(0) after the :input selector it will only grab the id for field_a_1, so how do I set it up so that I can pull just the field that I need to assign it to a variable?

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  • ggplot: showing % instead of counts in charts of categorical variables

    - by wishihadabettername
    I'm plotting a categorical variable and instead of showing the counts for each category value, I'm looking for a way to get ggplot to display the percentage of values in that category. Of course, it is possible to create another variable with the calculated percentage and plot that one, but I have to do it several dozens of times and I hope to achieve that in one command. I was experimenting with something like qplot (mydataf) + stat_bin(aes(n=nrow(mydataf), y=..count../n)) + scale_y_continuous(formatter="percent") but I must be using it incorrectly, as I got errors. To easily reproduce the setup, here's a simplified example: mydata <- c ("aa", "bb", null, "bb", "cc", "aa", "aa", "aa", "ee", null, "cc"); mydataf <- factor(mydata); qplot (mydataf); #this shows the count, I'm looking to see % displayed. In the real case I'll probably use ggplot instead of qplot, but the right way to use stat_bin still eludes me. Thank you. UPDATE: I've also tried these four approaches: ggplot(mydataf, aes(y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent'); ggplot(mydataf, aes(y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent') + geom_bar(); ggplot(mydataf, aes(x = levels(mydataf), y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent'); ggplot(mydataf, aes(x = levels(mydataf), y = (..count..)/sum(..count..))) + scale_y_continuous(formatter = 'percent') + geom_bar(); but all 4 give: Error: ggplot2 doesn't know how to deal with data of class factor The same error appears for the simple case of ggplot (data=mydataf, aes(levels(mydataf))) + geom_bar() so it's clearly something about how ggplot interacts with a single vector. I'm scratching my head, googling for that error gives a single result.

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