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Gtk: How can I get a part of a file in a textview with scrollbars relating to the full file

- by badgerman1

I'm trying to make a very large file editor (where the editor only stores a part of the buffer in memory at a time), but I'm stuck while building my textview object. Basically- I know that I have to be able to update the text view buffer dynamically, and I don't know hot to get the scrollbars to relate to the full file while the textview contains only a small buffer of the file. I've played with Gtk.Adjustment on a Gtk.ScrolledWindow and ScrollBars, but though I can extend the range of the scrollbars, they still apply to the range of the buffer and not the filesize (which I try to set via Gtk.Adjustment parameters) when I load into textview. I need to have a widget that "knows" that it is looking at a part of a file, and can load/unload buffers as necessary to view different parts of the file. So far, I believe I'll respond to the "change_view" to calculate when I'm off, or about to be off the current buffer and need to load the next, but I don't know how to get the scrollbars to have the top relate to the beginning of the file, and the bottom relate to the end of the file, rather than to the loaded buffer in textview. Any help would be greatly appreciated, thanks!

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Rails how to return a list of answers with a specific question_id

- by mytwocentsisworthtwocents

Let's say I have two Models, Answers and Questions (there are others, but irrelevant to the question). The models are as follows: Answer.rb class Answer < ActiveRecord::Base attr_accessible :description, :question_id has_one :question, :through => :user, :dependent => :destroy validates :description, :presence => true end Question.rb class Question < ActiveRecord::Base attr_accessible :budget, :description, :headline, :user_id, :updated_at, :created_at belongs_to :user has_many :answers validates :headline, :description, :user_id, :presence => true end I'd like to display on a page a list of all answers associated with a question, and only those questions. I got this far. I believe this variable finds all the questions in the database by the question_id (foreign key): @findanswers = Answer.all(params[:question_id]) And this one grabs the the id of the current question (this code will reside as an ERB on the page where the current question is located): @questionshow = Question.find(params[:id]) And now I'm stuck. How do I put the two together so that I list all the answers with the current question id?

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Java constructor using generic types

- by user37903

I'm having a hard time wrapping my head around Java generic types. Here's a simple piece of code that in my mind should work, but I'm obviously doing something wrong. Eclipse reports this error in BreweryList.java: The method initBreweryFromObject() is undefined for the type <T> The idea is to fill a Vector with instances of objects that are a subclass of the Brewery class, so the invocation would be something like: BreweryList breweryList = new BreweryList(BrewerySubClass.class, list); BreweryList.java package com.beerme.test; import java.util.Vector; public class BreweryList<T extends Brewery> extends Vector<T> { public BreweryList(Class<T> c, Object[] j) { super(); for (int i = 0; i < j.length; i++) { T item = c.newInstance(); // initBreweryFromObject() is an instance method // of Brewery, of which <T> is a subclass (right?) c.initBreweryFromObject(); // "The method initBreweryFromObject() is undefined // for the type <T>" } } } Brewery.java package com.beerme.test; public class Brewery { public Brewery() { super(); } protected void breweryMethod() { } } BrewerySubClass.java package com.beerme.test; public class BrewerySubClass extends Brewery { public BrewerySubClass() { super(); } public void androidMethod() { } } I'm sure this is a complete-generics-noob question, but I'm stuck. Thanks for any tips!

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Get value of selected field from a dropdown list

- by 47

I have this class in my model: class ServiceCharge(models.Model): name = models.CharField(max_length=30) amount = models.PositiveIntegerField() extends_membership = models.BooleanField(default=False) def __unicode__(self): return str(self.name) What I want to have is in the form for charging users a service charge, when a charge is selected from the dropdown menu, the two values for amount and extends_membership are updated on the form depending on the selected charge. My forms.py: class vModelChoiceField(forms.ModelChoiceField): def label_from_instance(self, obj): return "%s" % obj.name class PayServiceChargeForm(PaymentsForm): service_charge = vModelChoiceField(queryset=ServiceCharge.objects.all(), empty_label=" ") class Meta(PaymentsForm.Meta): exclude = ('member', 'payment_type', 'transacted_by', 'description') Then the form template: <table border="0"> <tr> <td><strong>{% trans "Service Charge" %}</strong></td> <td>{{ form.service_charge }}</td> <td><strong>{% trans "Extends Membership" %}</strong></td> <td>{{ form.extends_membership }}</td> </tr> <tr> <td valign="top"><strong>{% trans "Expiry Date" %}</strong></td> <td valign="top">{{ form.expiry_date }}</td> <td valign="top"><strong>{% trans "Amount" %}</strong></td> <td>{{ form.amount }}</td> </tr> </table> I was trying out some jQuery but I got stuck after getting the currently selected charge: <script type="text/javascript"> $(document).ready(function(){ $("#id_service_charge").change(onSelectChange); }); function onSelectChange(){ var selected = $("#id_service_charge option:selected"); var output = ""; if(selected.val() != 0){ charge = selected.val(); .... (update values) .... } } </script>

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C++ class derivation and superconstructor confusion

- by LukeN

Hey, in a tutorial C++ code, I found this particular piece of confusion: PlasmaTutorial1::PlasmaTutorial1(QObject *parent, const QVariantList &args) : Plasma::Applet(parent, args), // <- Okay, Plasma = namespace, Applet = class m_svg(this), // <- A member function of class "Applet"? m_icon("document") // <- ditto? { m_svg.setImagePath("widgets/background"); // this will get us the standard applet background, for free! setBackgroundHints(DefaultBackground); resize(200, 200); } I'm not new to object oriented programming, so class derivation and super-classes are nothing complicated, but this syntax here got me confused. The header file defines the class like this: class PlasmaTutorial1 : public Plasma::Applet { Similar to above, namespace Plasma and class Applet. But what's the public doing there? I fear that I already know the concept but don't grasp the C++ syntax/way of doing it. In this question I picked up that these are called "superconstructors", at least that's what stuck in my memory, but I don't get this to the full extend. If we glance back at the first snippet, we see Constructor::Class(...) : NS::SuperClass(...), all fine 'till here. But what are m_svg(this), m_icon("document") doing there? Is this some kind of method to make these particular functions known to the derivated class? Is this part of C++ basics or more immediate? While I'm not completly lost in C++, I feel much more at home in C :) Most of the OOP I have done so far was done in D, Ruby or Python. For example in D I would just define class MyClass : MySuperClass, override what I needed to and call the super class' constructor if I'd need to.

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C++ Boolean problem (comparison between two arrays)

- by Martin

Hello! I have a problem to do. I already did some part of it, however I stuck and don't know exactly what to do next. The question: " You are given two arrays of ints, named A and B. One contains AMAXELEMENTS and the other contains BMAXELEMENTS. Write a Boolean-valued function that returns true if there is at least one point in A that is the same as a point in B, and false if there is no match between two arrays. " The two arrays are made up by me, I think if I know how to compare two arrays I will be fine, and I will be able to finish my problem. This is what I have so far (I changed AMAXELEMENTS to AMAX, and BMAXELEMENTS to BMAX): #include <iostream> using namespace std; int main(){ const int AMAX=5, BMAX=6; int i; bool c1=true,c2=false; int A[AMAX]={2,4,1,5,9}; int B[BMAX]={9,12,32,43,23,11}; for(i=0;i<BMAX;i++) if (B[i]==A[i]) // <---- I think this part has to look different, but I can't figure it out. cout<<c1<<endl; else cout<< c2<<endl; return 0; }

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How can I use io.StringIO() with the csv module?

- by Tim Pietzcker

I tried to backport a Python 3 program to 2.7, and I'm stuck with a strange problem: >>> import io >>> import csv >>> output = io.StringIO() >>> output.write("Hello!") # Fail: io.StringIO expects Unicode Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unicode argument expected, got 'str' >>> output.write(u"Hello!") # This works as expected. 6L >>> writer = csv.writer(output) # Now let's try this with the csv module: >>> csvdata = [u"Hello", u"Goodbye"] # Look ma, all Unicode! (?) >>> writer.writerow(csvdata) # Sadly, no. Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: unicode argument expected, got 'str' According to the docs, io.StringIO() returns an in-memory stream for Unicode text. It works correctly when I try and feed it a Unicode string manually. Why does it fail in conjunction with the csv module, even if all the strings being written are Unicode strings? Where does the str come from that causes the Exception? (I do know that I can use StringIO.StringIO() instead, but I'm wondering what's wrong with io.StringIO() in this scenario)

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Why do I get Error#2036 in flash AS3 and how to solve this?

- by sydas

I'm currently building an application in flash in relation to RSS/XML feeds for a project. I'm stuck at the moment because I keep getting this error: Error opening URL 'http://distilleryimage6.instagram.com/.jpg' Error #2044: Unhandled IOErrorEvent:. text=Error #2036: Load Never Completed. I know my string picURL is not functioning properly, but am I missing something that makes it not functional? This is my code: package { import flash.display.*; import flash.events.*; import flash.net.*; public class instagramFeed extends MovieClip { //link to #rit xml loader public var ritFileRequest = new URLRequest("http://instagram.com/tags/rit/feed/recent.rss"); public var ritXmlLoader = new URLLoader(); //link to #rochester xml loader // same as above public variables public function instagramFeed() { // constructor code trace("About to load..."); //Loads #rit hashtag xml data. ritXmlLoader.load(ritFileRequest); ritXmlLoader.addEventListener(Event.COMPLETE, displayRITInfo); } //focuses on data with #rit hashtag public function displayRITInfo(e:Event):void{ var ritInstagramData:XML = new XML(ritXmlLoader.data); var ritInfoList:XMLList = ritInstagramData.elements().item; trace(ritInfoList); //load the image var ritPic:String = ritInfoList.*::condition.@code; var picURL:String = "http://distilleryimage6.instagram.com/" + ritPic + ".jpg"; trace(picURL); //show the image on the stage! var ritImageRequest:URLRequest = new URLRequest(picURL); var ritImageLoader:Loader = new Loader(); ritImageLoader.load(ritImageRequest); addChild(ritImageLoader); ritImageLoader.x=200; ritImageLoader.y=100; ritImageLoader.scaleX = 3; ritImageLoader.scaleY = 3; } } }

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Entities used to serialize data have changed. How can the serialized data be upgraded for the new entities?

- by i8abug

Hi, I have a bunch of simple entity instances that I have serialized to a file. In the future, I know that the structure of these entities (ie, maybe I will rename Name to Header or something). The thing is, I don't want to lose the data that I have saved in all these old files. What is the proper way to either load the data from the old entities into new entities upgrade the old files so that they can be used with new entities Note: I think I am stuck with binary serialization, not xml serialization. Thanks in advance! Edit: So I have an answer for the case I have described. I can use a dataContractSerializer and do something like [DataMember("bar")] private string foo; and change the name in the code and keep the same name that was used for serialization. But what about the following additional cases: The original entity has new members which can be serialized Some serialized members that were in the original entity are removed Some members have actually changed in function (suppose that the original class had a FirstName and LastName member and it has been refactored to have only a FullName member which combines the two) To handle these, I need some sort of interpreter/translator deserialization class but I have no idea what I should use

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Connect 4 C# (How to draw the grid)

- by Matt Wilde

I've worked out most of the code and have several game classes. The one bit I'm stuck on at the moment, it how to draw the actual Connect 4 grid. Can anyone tell me what's wrong with this for loop? I get no errors but the grid doesn't appear. I'm using C#. private void Drawgrid() { Brush b = Brushes.Black; Pen p = Pens.Black; for (int xCoor = XStart, col = 0; xCoor < XStart + ColMax * DiscSpace; xCoor += DiscSpace, col++) // x coordinate beginning; while the x coordinate is smaller than the max column size, times it by // the space between each disc and then add the x coord to the disc space in order to create a new circle. for (int yCoor = YStart, row = RowMax - 1; yCoor < YStart + RowMax * DiscScale; yCoor += DiscScale, row--) { switch (Grid.State[row, col]) { case GameGrid.Gridvalues.Red: b = Brushes.Red; break; case GameGrid.Gridvalues.Yellow: b = Brushes.Yellow; break; case GameGrid.Gridvalues.None: b = Brushes.Aqua; break; } MainDisplay.DrawEllipse(p, xCoor, yCoor, 50, 50); MainDisplay.FillEllipse(b, xCoor, yCoor, 50, 50); } Invalidate(); } Thanks.

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iTunes Connect uploading issue

- by CindySeattle

Too bad that iTunes Connect changed its behavior recently. I'm providing an update to an existing app. I submitted new binary using the Loader without problem on the first try. Then I discovered that different from before, one has to reject the binaries in order to change screenshots. Too bad that the update is in the status of "In Review". Well, I have to rejected my binaries and begin to upload new screenshots, because I don't want to display screenshots of previous version. The new screen shots are uploaded but I'm stuck in "Developer rejected" status. Meaning I cannot upload the binaries and not able to change screenshots from that time on. The following error will appear when click Save Changes in either situations. "There was an error saving changes. Please try again later or contact iTunes Connect Support at [email protected]." I checked the source of the error page and think it's this error id="lcBoxWrapperHeaderTextUpdaterContainer" action="/WebObjects/iTunesConnect.woa/wo/7.0.0.9.7.7.1.1.1.1" errorId="ajaxContainerError" I have reported iTune Connect via the "Contact us" link on this issue but not get any response back for 2 days already. Very disappointing. Did anybody experience similar issue? How did you resolve this?

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trouble with custom 'Text Bubble' component (examples included)

- by gmoniey

I'm trying to use a custom Text component to show a series of comments. I got the original idea from: http://www.eonflex.com/?p=40 I've got the base case working but I am stuck with 2 problems I cant seem to figure out: Since I am drawing around the text, the actual height of each bubble is greater than that of the Text field, as a result, the last bubble is always chopped off. I have tried explicitly overriding the height getter, and adding some padding, but I cant seem to get it right. You can see an example here: http://test.lambandtunafish.com/bubbles/CommentTest.swf In my layout, I have 2 VBoxes (one nested inside the other). The first vbox shows a form where the user can enter a comment, and the second box has all the comments. In order to ensure that the scrollbars only show up on the second box, I set minHeight="0" on the nested VBox, but then for some reason, some comments' text is shifted to the right. You can see an example here (look at the first comment): http://test.lambandtunafish.com/bubbles/CommentTest-minHeight.swf Rather than posting the code here, I've provided some links: Container: http://test.lambandtunafish.com/bubbles/CommentTest.mxml Bubble: http://test.lambandtunafish.com/bubbles/CommentBubble.as If anyone has any ideas, I would appreciate it. Thanks!

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Help converting subquery to query with joins

- by Tim

I'm stuck on a query with a join. The client's site is running mysql4, so a subquery isn't an option. My attempts to rewrite using a join aren't going too well. I need to select all of the contractors listed in the contractors table who are not in the contractors2label table with a given label ID & county ID. Yet, they might be listed in contractors2label with other label and county IDs. Table: contractors cID (primary, autonumber) company (varchar) ...etc... Table: contractors2label cID labelID countyID psID This query with a subquery works: SELECT company, contractors.cID FROM contractors WHERE contractors.complete = 1 AND contractors.archived = 0 AND contractors.cID NOT IN ( SELECT contractors2label.cID FROM contractors2label WHERE labelID <> 1 AND countyID <> 1 ) I thought this query with a join would be the equivalent, but it returns no results. A manual scan of the data shows I should get 34 rows, which is what the subquery above returns. SELECT company, contractors.cID FROM contractors LEFT OUTER JOIN contractors2label ON contractors.cID = contractors2label.cID WHERE contractors.complete = 1 AND contractors.archived = 0 AND contractors2label.labelID <> 1 AND contractors2label.countyID <> 1 AND contractors2label.cID IS NULL

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Windows XP: RegSvr32 /i:[cmdline]: What exactly is "Command line" in this case?

- by Kim

I am trying to register a dll using regsvr32 in a cmd window. I do this on an administrator account, but I need this dll to be registered for all the users. Turns out regsvr32 does not do that, it only registers for your current user. Well, when you use it this way anyways: "regsvr32 /i "C:\MyDll.dll"" What happens; The entry is added to Local_User, and Classes in the registry, but not Local_Machine. The msdn article on regsvr32 says it also takes a [cmdline] when using the /i option. But the article fails to specify what I can put in place of [cmdline]. Google is refusing to help me as well, so I'm a bit stuck on this. I realize this is not exactly on the topic of programming, but this is something programmers might know, so... Has anyone run into this before? Perhaps someone knows how this [cmdline] tag works? Are there any other ways to add this dll to all users? (Apart from editing the registry manually that is.) Any insight would be greatly appreciated!

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Changing the value of a variable

- by neirpycc

I'm trying to build a simple scoring app but I'm running into a problem trying to keep it so I don't have to repeat a bunch of code to deal with each 'base' individually. The basic idea is that when I click a button the script will; 1) grab the ID of said button 2) split the ID into two parts - (a) the bases name and (b) the button type (plus/minus) 3) if it's plus - add to the bases score, if it's minus - subtract from the bases score 4) update the assigned div with the new value The part I'm stuck at is adding and subtracting. I can't seem to get this to work. Here is the code: $('.base button').click(function() { var b1Score = 0; var b2Score = 0; var b3Score = 0; var b4Score = 0; var b5Score = 0; var clickedButton = $(this).attr('id'); var buttonInfo = clickedButton.split('-'); var baseClicked = buttonInfo[0]; var baseDirection = buttonInfo[1]; var baseDiv = ('#' + baseClicked); console.log('You clicked ' + clickedButton + '.'); if (baseDirection.indexOf('plus') >= 0) { console.log('Increasing ' + baseClicked + '!'); ++; $(baseDiv).val(); } else { console.log('Decreasing ' + baseClicked + '!'); --; $(baseDiv).val(); } }); ++; and --; are placeholders for where the adding and subtracting needs to happen. I just can't figure out how to get it to add or subtract from the correct value. Any help is appreciated. Thanks.

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Storing multiple discarded datas in a single variable using a string accumulator

- by dan

For an assignment for my intro to python course, we are to write a program that generates 100 sets of x,y coordinates. X must be a float between -100.0 and 100.0 inclusive, but not 0. Y is Y = ((1/x) * 3070) but if the absolute value of Y is greater than 100, both numbers must be discarded (BUT STORED) and another set generated. The results must be displayed in a table, and then after the table, the discarded results must be shown. The teacher said we should use a "string accumulator" to store the discarded data. This is what I have so far, and I'm stuck at storing the discarded data. # import random.py import random # import math.py import math # define main def main(): x = random.uniform(-100.0, 100.0) while x == 0: x = random.uniform(-100.0, 100.0) y = ((1/x) * 3070) while math.fabs(y) > 100: xDiscarded = yDiscarded = y = ((1/x) * 3070) As you can see, I run into the problem of when abs(y) 100, I'm not too sure how to store the discarded data and let it accumulate every time abs(y) 100. I'm cool with the data being stored as "351.2, 231.1, 152.2" I just don't know how to turn the variable into a string and store it. We haven't learned arrays yet so I can't do that. Any help would be much appreciated. Thanks!

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How to get jQuery to find the first list-item, rather than all list-items?

- by ricebowl

I'm trying to implement a basic jQuery infinite carousel. As much for the learning process as for anything else (as a rule I'm not a fan of re-inventing wheels, but...I have to learn somehow, might as well start with the basics). I've managed to get the list to animate left happily enough, but I'm stuck when it comes to selecting the first element of the list. I've tried to use: $('ul#services > li:first'); $('ul#services > li:first-child'); $('ul#services > li').eq([0]); (xhtml below), In each case a console.log(first) (the var name used) returns all of the list-items. Am I doing something blatantly, and obviously, wrong? The eventual plan is to clone the first li, append it to the parent ul, remove the li from the list and allow the list to scroll infinitely. It's just a list of services rather than links so I'm not -at the moment- planning to have scroll or left/right functionality. Current xhtml: <div class="wrapper"> <ul id="services">  <li>one</li ><li>two</li ><li>three</li ><li>four</li ><li>five</li ><li>six</li ><li>seven</li ><li>eight</li ><li>nine</li ><li>ten</li> </ul> </div>

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Why doesn't PHP's oci_connect return false?

- by absolethe

I have a situation in which we have two production databases that synchronize with one other. Server One is considered the primary. Sometimes due to maintenance or a disaster Server Two will become primary. In some of our code that means we have to manually go in and edit the server name for database connections. I find this annoying, so the last thing I wrote I put the server information for both and set up a loop. If oci_connect failed on the Server One 3 times it would move on to Server Two. If Server Two failed 3 times it would notify the user a connection couldn't be made. This has worked fine most times we've had the situation of switching the servers. Yesterday, for example, it worked fine. Today it didn't. It just sat and spun endlessly. No error in the PHP error log. No failure to move on from. No error output to the screen. Nothing for 5 minutes. So then I had to manually edit the stupid config file. I asked what could possibly be different and I was told "yesterday the database was down, but not the server. today the server is down." Okay...? But I don't see a distinction. I would expect oci_connect to return false if it can't establish any sort of communication with the server. I'd expect it to timeout and error. Not just pass it on when it receives an error code from the server. What if there's a network problem, for example? Is this a bug in oci_connect or is there a possibility that something in our PHP configuration gives oci_connect a crazily long timeout? If it is a sort of "bug" is there some way I can check to see if the server is up first? Like a ping? (Of course when I did a ping through the command prompt I got a response from Server One and then was told, "it's back now" although I am skeptical about the timing on that.) Anyway, if anyone could shed some light on why oci_connect might run endlessly without failing and how to keep it from doing so I'd be grateful. -- Edit: My code looks like the examples on PHP.net only in some loops. $count = count($servers); for($i = 0; $i < $count; $i++){ if((!isset($connection)) || ($connection == false)){ // Attempt to connect to the oracle database $connection = @oci_connect($servers[$i]["user"], $servers[$i]["pass"], $servers[$i]["conid"]) or ($conn_error = oracle_error()); // Try again if there was a failure if(($connection == false) || (isset($con_error))){ // Three (two more) tries per alternative for($j = $st; $j < $fn; $j++){ // Try again to connect $connection = @oci_connect($servers[$i]["user"], $servers[$i]["pass"], $servers[$i]["conid"]) or ($conn_error = oracle_error()); } // for($j = 2; $j < 4; $j++) } // if($connection == false) } // if(!isset($connection) || ($connection == false)) } // for($i = 0; $i < $count; $i++)

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How to check user input for correct formatting

- by Arcadian

This is what i've come up with so far private void CheckFormatting() { StringReader objReaderf = new StringReader(txtInput.Text); List<String> formatTextList = new List<String>(); do { formatTextList.Add(objReaderf.ReadLine()); } while (objReaderf.Peek() != -1); objReaderf.Close(); for (int i = 0; i < formatTextList.Count; i++) { } } What it is designed to do is check that the user has entered their information in this format Gxx:xx:xx:xx JGxx where "x" can be any integer. As you can see the user inputs their data into a multi-line textbox. i then take that data and enter it into a list. the next part is where i'm stuck. i create a for loop to go through the list line by line, but i guess i will also need to go through each line character by character. How do i do this? or is there a faster way of doing it? thanks in advance

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Order words by number of letters, then place words neatly

- by bmaster

I have a list of words in javascript similar to this: var words = ["mine", "minute", "mist", "mixed", "money", "monkey", "month", "moon", "morning", "mother", "motion", "mountain", "mouth", "move", "much", "muscle", "music", "nail", "name", "narrow", "nation", "natural", "near", "necessary", "neck", "need", "needle", "nerve", "net", "new", "news", "night"]; The words can be 1-25? letters long. I have a div id="words", with a set width of 700px (but I might change it from this). Using css/javascript/jquery, how can I make it: Order the words by number of letters Place the words inside the div tag, left to right, but so that there are no gaps at the right edge of the words div, and there is even spacing between words on a line. Each word should have a border around it and a background. Like this: |reallylongwordssdf shorterwordfdf dfsdfsdfsdf sdfsdfsdf| |sdfsdfsdf sdffsdop sdfjpogs sdfsds dfsdsd dfsdsd dfsdsd| I really have no idea where to begin with this. Perhaps I could manage to write code to order the words by number of letters, but after that, I'd be stuck. Edit: I forgot to add, the words must be links.

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2-column table with two foreign keys. Performance/design question.

- by Emanuel

Hello everyone! I recently ran into a quite complex problem and after looking around a lot I couldn't find a solution to it. I've found answers to my questions many times before on stackoverflow.com, so I decided to post here. So I'm making a user/group managment system for a web-based project, and I'm storing all related data into a postgreSQL database. This system relies on three tables: USERS GROUPS GROUP_USERS The two first tables simply define all the users and all the groups on the site, and the last table, GROUP_USERS, stores the groups every user is part of. It only has two columns: USER_ID GROUP_ID Since every user can be a member of several groups, I decided to make a separate table for this purpose, rather than storing a comma separated column in the USERS-table. Now, both columns are foreign keys, and I want to make them both primary keys as well, this since each combination of USER_ID and GROUP_ID has to be unique, and if I give them the constraint UNIQUE pgAdmin tells me that each table should have at least one Primary key. But now I am stuck with what seems to be a lot of indexes and relations to a very small table only containing numbers. In the end, I want this table to be as fast as possible, even if containing tens of thousands of rows. Size on disk shouldn't be a problem since its just all numbers anyway, but it feels quite stupid to have a full-sized index refering to a smaller table. Should I stick with my current solution, store comma-separated values in a column in the USERS-table or is there any other solution I should be aware of. PS. I don't want to use an array-column, even if they are supported by postgreSQL. I want to be as generic as possible so I can switch database later on, if necessary. EDIT: I other words, will using a compound primary key and two foreign keys in one table with only two columns have a negative impact on performance rather than the opposite due to the size of the generated index? Thank you!

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How to convert a byte array of 19200 bytes in size where each byte represents 4 pixels (2 bits per p

- by Klinger

I am communicating with an instrument (remote controlling it) and one of the things I need to do is to draw the instrument screen. In order to get the screen I issue a command and the instrument replies with an array of bytes that represents the screen. Below is what the instrument manual has to say about converting the response to the actual screen: The command retrieves the framebuffer data used for the display. It is 19200 bytes in size, 2-bits per pixel, 4 pixels per byte arranged as 320x240 characteres. The data is sent in RLE encoded form. To convert this data into a BMP for use in Windows, it needs to be turned into a 4BPP. Also note that BMP files are upside down relative to this data, i.e. the top display line is the last line in the BMP. I managed to unpack the data, but now I am stuck on how to actually go from the unpacked byte array to a bitmap. My background on this is pretty close to zero and my searches have not revealed much either. I am looking for directions and/or articles I could use to help me undestand how to get this done. Any code or even pseudo code would also help. :-) So, just to summarize it all: How to convert a byte array of 19200 bytes in size, where each byte represents 4 pixels (2 bits per pixel), to a bitmap arranged as 320x240 characters. Thanks in advance.

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I want to add and remove items from a menu with PHP.

- by CDeanMartin

This menu will need to be updated daily. <html><head></head><body> <h1> Welcome to Burgerama </h1> <?php include("menuBuilder.php"); showBurgerMenu(); ?> </body></html> Menu items are stored in the database. Items have a display field; if it is on, the item should be displayed on the menu. The menu only displays 4 or 5 "specials" at a time, and the manager needs to change menu items easily. I want to make a menu editing page like this: <?php include("burger_queries.php"); dbconnect("burger_database"); foreach($menuItem in burger_database) { echo createToggleButton($menuItem); } ?> .. with a toggle button for each menu item. Ideally the button will be labeled with the menu item, in blue if the item is "on", and red if the item is "off." Clicking the button switches between "on" and "off" I am stuck trying to a get a button to execute an UPDATE query on its corresponding menu item.

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how am I supposed to call the function?

- by user1816768

I wrote a program which tells you knight's movement (chess). For example if I wanted to know all possible moves, I'd input: possibilites("F4") and I'd get ['D3', 'D5', 'E2', 'E6', 'G2', 'G6', 'H3', 'H5'] as a result, ok I did that, next, I had to write a function in which you input two fields and if those fields are legal, you'd get True and if they're not you'd get False(I had to use the previous function). For example: legal("F4","D3") >>>True code: def legal(field1,field2): c=possibilities(field1) if field1 and field2 in a: return True return False I'm having a problem with the following function which I have to write: I have to put in path of the knight and my function has to tell me if it's legal path, I'm obliged to use the previous function. for example: >>> legal_way(["F3", "E1", "G2", "H4", "F5"]) True >>> legal_way(["F3", "E1", "G3", "H5"]) False >>> legal_way(["B4"]) True I know I have to loop through the list and put first and second item on it in legal(field1,field2) and if it's false, everything is false, but if it's true I have to continue to the end, and this has to work also if I have only one field. I'm stuck, what to do? def legal_way(way): a=len(way) for i in range(0,a-2): if a==1: return true else if legal(way[i],way[i+1]: return True return False and I get True or index out of range

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Write out to text file using T-SQL

- by sasfrog

I am creating a basic data transfer task using TSQL where I am retrieving certain records from one database that are more recent than a given datetime value, and loading them into another database. This will happen periodically throughout the day. It's such a small task that SSIS seems like overkill - I want to just use a scheduled task which runs a .sql file. Where I need guidance is that I need to persist the datetime from the last run of this task, then use this to filter the records next time the task runs. My initial thought is to just store the datetime in a text file, and update (overwrite) it as part of the task each time it runs. I can read the file in without problems using T-SQL, but writing back out has got me stuck. I've seen plenty of examples which make use of a dynamically-built bcp command, which is then executed using xp_cmdshell. Trouble is, security on the server I'm deploying to precludes the use of xp_cmdshell. So, my question is, are there other ways to simply write a datetime value to a file using TSQL, or should I be thinking about a different approach? EDIT: happy to be corrected about SSIS being "overkill"...

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