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  • Most "thorough" distribution of points around a circle

    - by hippietrail
    This question is intended to both abstract and focus one approach to my problem expressed at "Find the most colourful image in a collection of images". Imagine we have a set of circles, each has a number of points around its circumference. We want to find a metric that gives a higher rating to a circle with points distributed evenly around the circle. Circles with some points scattered through the full 360° are better but circles with far greater numbers of points in one area compared to a smaller number in another area are less good. The number of points is not limited. Two or more points may coincide. Coincidental points are still relevant. A circle with one point at 0° and one point at 180° is better than a circle with 100 points at 0° and 1000 points at 180°. A circle with one point every degree around the circle is very good. A circle with a point every half degree around the circle is better. In my other (colour based question) it was suggested that standard deviation would be useful but with caveat. Is this a good suggestion and does it cope with the closeness of 359° to 1°?

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  • Why do C# containers and GUI classes use int and not uint for size related members ?

    - by smerlin
    I usually program in C++, but for school i have to do a project in C#. So i went ahead and coded like i was used to in C++, but was surprised when the compiler complained about code like the following: const uint size = 10; ArrayList myarray = new ArrayList(size); //Arg 1: cannot convert from 'uint' to 'int Ok they expect int as argument type, but why ? I would feel much more comfortable with uint as argument type, because uint fits much better in this case. Why do they use int as argument type pretty much everywhere in the .NET library even if though for many cases negative numbers dont make any sense (since no container nor gui element can have a negative size). If the reason that they used int is, that they didnt expect that the average user cares about signedness, why didnt they add overloads for uint additonally ? Is this just MS not caring about sign correctness or are there cases where negative values make some sense/ carry some information (error code ????) for container/gui widget/... sizes ?

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  • Moving to an arbitrary position in a file in Python

    - by B Rivera
    Let's say that I routinely have to work with files with an unknown, but large, number of lines. Each line contains a set of integers (space, comma, semicolon, or some non-numeric character is the delimiter) in the closed interval [0, R], where R can be arbitrarily large. The number of integers on each line can be variable. Often times I get the same number of integers on each line, but occasionally I have lines with unequal sets of numbers. Suppose I want to go to Nth line in the file and retrieve the Kth number on that line (and assume that the inputs N and K are valid --- that is, I am not worried about bad inputs). How do I go about doing this efficiently in Python 3.1.2 for Windows? I do not want to traverse the file line by line. I tried using mmap, but while poking around here on SO, I learned that that's probably not the best solution on a 32-bit build because of the 4GB limit. And in truth, I couldn't really figure out how to simply move N lines away from my current position. If I can at least just "jump" to the Nth line then I can use .split() and grab the Kth integer that way. The nuance here is that I don't just need to grab one line from the file. I will need to grab several lines: they are not necessarily all near each other, the order in which I get them matters, and the order is not always based on some deterministic function. Any ideas? I hope this is enough information. Thanks!

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  • barebones sort algorithm

    - by user309322
    i have been asked to make a simple sort aglorithm to sort a random series of 6 numbers into numerical order. However i have been asked to do this using "Barebones" a theoretical language put forward in the Book Computer Science an overview. Some information on the language can be found here http://www.brouhaha.com/~eric/software/barebones/ Just to clarify i am a student teacher and have been doing anaysis on "mini-programing languages" and their uses in a teaching environment, i suggested to my tutor that i look at barebones and asked what sort of exmaple program i should write . He suggested a simple sort algorithm. Now since looking at the language i cant understand how i can do this without using arrays and if statements. The code to swap the value of variables would be while a not 0 do; incr Aux1; decr a; end; while b not 0 do; incr Aux2 decr b end; while Aux1 not 0 do; incr a; decr Aux1; end; while Aux2 not 0 do; incr b; decr Aux2; end; however the language does not provide < or operators

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  • Ideas in implenting the following entry form in ASP.NET MVC 2

    - by KiD0M4N
    Hi guys, I have a very simple data entry form to implement. It looks like this: Obviously I have mocked out the actual requirements but the essence is similar. Entering a name and clicking history should bring up a pop up pointing to the url '/student/viewhistory/{name}' Name and age are required fields The sub form (in the mockup) with Class (a drop down, containing the numbers 1 - 10) and Subject (containing A - D, say) form a unique pair of values for which a score is required. So, selecting the Class and Subject, entering a score and clicking on Add should 'add' this record for the student. Then the user should be able to click Save (to persist the entry to the database) or be able to add further (class, subject, score) pairs to the entry. Any ideas how to smartly implement this? (I am coming from a DWH field... so thinking in a stateless manner is slightly foreign to me.) Any help is appreciated. I would imagine a smart use of jQuery would give a easy solution. Regards, Karan

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  • How to encrypt/decrypt a file in Java?

    - by Petike
    Hello, I am writing a Java application which can "encrypt" and consequently "decrypt" whatever binary file. I am just a beginner in the "cryptography" area so I would like to write a very simple application for the beginning. For reading the original file, I would probably use the java.io.FileInputStream class to get the "array of bytes" byte originalBytes[] of the file. Then I would probably use some very simple cipher, for example "shift up every byte by 1" and then I would get the "encrypted" bytes byte encryptedBytes[] and let's say that I would also set a "password" for it, for example "123456789". Next, when somebody wants to "decrypt" that file, he has to enter the password ("123456789") first and after that the file could be decrypted (thus "shift down every byte by 1") and consequently saved to the output file via java.io.FileOutputStream I am just wondering how to "store" the password information to the encrypted file so that the decrypting application knows if the entered password and the "real" password equals? Probably it would be silly to add the password (for example the ASCII ordinal numbers of the password letters) to the beginning of the file (before the encrypted data). So my main question is how to store the password information to the encrypted file?

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  • ObjC internals. Why my duck typing attempt failed?

    - by Piotr Czapla
    I've tried to use id to create duck typing in objective-c. The concept looks fine in theory but failed in practice. I was unable to use any parameters in my methods. The methods were called but parameters were wrong. I was getting BAD_ACESS for objects and random values for primitives. I've attached a simple example below. The question: Does any one knows why the methods parameters are wrong? What is happening under the hood of the objective-c? Note: I'm interest in the details. I know how to make the example below work. An example: I've created a simple class Test that is passed to an other class using property id test. @implementation Test - (void) aSampleMethodWithFloat:(float) f andInt: (int) i { NSLog(@"Parameters: %f, %i\n", f, i); } @end Then in the class the following loop is executed: for (float f=0.0f; f < 100.0f ; f += 0.3f) { [self.test aSampleMethodWithOneFloatParameter: f]; // warning: no method found. } Here is the output that I'm getting. As you can see the method was called but the parameters were wrong. Parameters: 0.000000, 0 Parameters: -0.000000, 1069128089 Parameters: -0.000000, 1070176665 Parameters: 2.000000, 1070805811 Parameters: -0.000000, 1071225241 Parameters: 0.000000, 1071644672 Parameters: 2.000000, 1071854387 Parameters: 36893488147419103232.000000, 1072064102 Parameters: -0.000000, 1072273817 Parameters: -36893488147419103232.000000, 1072483532

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  • struct and rand()

    - by teoz
    I have a struct with an array of 100 int (b) and a variable of type int (a) I have a function that checks if the value of "a" is in the array and i have generated the array elements and the variable with random values. but it doesn't work can someone help me fix it? #include <stdio.h> #include <stdlib.h> #include <time.h> typedef struct { int a; int b[100]; } h; int func(h v){ int i; for (i=0;i<100;i++){ if(v.b[i]==v.a) return 1; else return 0; } } int main(int argc, char** argv) { h str; srand(time(0)); int i; for(i=0;0<100;i++){ str.b[i]=(rand() % 10) + 1; } str.a=(rand() % 10) + 1; str.a=1; printf("%d\n",func(str)); return 0; }

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  • Reading bmp file for encrypting and decrypting txt file into it

    - by Shantanu Gupta
    I am trying to read a bmp file in C++(Turbo). But i m not able to print binary stream. I want to encode txt file into it and decrypt it. How can i do this. I read that bmp file header is of 54 byte. But how and where should i append txt file in bmp file. ? I know only Turbo C++, so it would be helpfull for me if u provide solution or suggestion related to topic for the same. int main() { ifstream fr; //reads ofstream fw; // wrrites to file char c; int random; clrscr(); char file[2][100]={"s.bmp","s.txt"}; fr.open(file[0],ios::binary);//file name, mode of open, here input mode i.e. read only if(!fr) cout<<"File can not be opened."; fw.open(file[1],ios::app);//file will be appended if(!fw) cout<<"File can not be opened"; while(!fr) cout<<fr.get(); // error should be here. but not able to find out what error is it fr.close(); fw.close(); getch(); } This code is running fine when i pass txt file in binary mode

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  • Open txt files from a directory, compare the values, and output the top 15 in PHP

    - by Anon
    Hello, I recently designed a referral game website for the fun of it. There's a simple MySQL user system with a email verification. It's using the UserCake user management system. On top of this i added a php page that the user could give to "victims" that when they visit it they get "infected" and can infect other users or "victims". This page uses GET to get the username from the url. I have a folder that when a user registers it creates a file with 4 digits and then the username. (ex; 0000Username.txt) All the numbers are the same, it's just so that if a user discovers the folder they won't be able to find the files. There is also a txt file in the same format with IPS in the name. (ex; 0000IPSUsername.txt) The file when visited gets the username from the url, then checks if the text file for that username exists. If the username is present in the url, and a valid user it opens the IPS file and adds the IP of the visitor, then opens the user text file, takes the value and adds one to it, and saves. At the end it makes the difference between saying "You are infected, Username has infected (amount) people." or just you have been infected. Now to what i need! I need to add a hi-scores to the website so people can compete to be the one with the most "infections". I thought i could use readdir to get a list of the files and open them with the value in an array, but i need it to also strip the username from the file name. It would be best if it just saves to a text file like "Username | value" because then i can add echo's of the html tags and have it include the file in the page i want it to be one. Many thanks in advance.

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  • Using lambda expressions and linq

    - by Andy
    So I've just started working with linq as well as using lambda expressions. I've run into a small hiccup while trying to get some data that I want. This method should return a list of all projects that are open or in progress from Jira Here's the code public static List<string> getOpenIssuesListByProject(string _projectName) { JiraSoapServiceService jiraSoapService = new JiraSoapServiceService(); string token = jiraSoapService.login(DEFAULT_UN, DEFAULT_PW); string[] keys = { getProjectKey(_projectName) }; RemoteStatus[] statuses = jiraSoapService.getStatuses(token); var desiredStatuses = statuses.Where(x => x.name == "Open" || x.name == "In Progress") .Select(x=>x.id); RemoteIssue[] AllIssues = jiraSoapService.getIssuesFromTextSearchWithProject(token, keys, "", 99); IEnumerable<RemoteIssue> openIssues = AllIssues.Where(x=> { foreach (var v in desiredStatuses) { if (x.status == v) return true; else return false; } return false; }); return openIssues.Select(x => x.key).ToList(); } Right now this only select issues that are "Open", and seems to skip those that are "In Progress". My question: First, why am I only getting the "Open" Issues, and second is there a better way to do this? The reason I get all the statuses first is that the issue only stores that statuses ID, so I get all the statuses, get the ID's that match "Open" and "In Progress", and then match those ID numbers to the issues status field.

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  • How do you verify that 2 copies of a VB 6 executable came from the same code base?

    - by Tim Visher
    I have a program under version control that has gone through multiple releases. A situation came up today where someone had somehow managed to point to an old copy of the program and thus was encountering bugs that have since been fixed. I'd like to go back and just delete all the old copies of the program (keeping them around is a company policy that dates from before version control was common and should no longer be necessary) but I need a way of verifying that I can generate the exact same executable that is better than saying "The old one came out of this commit so this one should be the same." My initial thought was to simply MD5 hash the executable, store the hash file in source control, and be done with it but I've come up against a problem which I can't even parse. It seems that every time the executable is generated (method: Open Project. File Make X.exe) it hashes differently. I've noticed that Visual Basic messes with files every time the project is opened in seemingly random ways but I didn't think that would make it into the executable, nor do I have any evidence that that is indeed what's happening. To try to guard against that I tried generating the executable multiple times within the same IDE session and checking the hashes but they continued to be different every time. So that's: Generate Executable Generate MD5 Checksum: md5sum X.exe > X.md5 Verify MD5 for current executable: md5sum -c X.md5 Generate New Executable Verify MD5 for new executable: md5sum -c X.md5 Fail verification because computed checksum doesn't match. I'm not understanding something about either MD5 or the way VB 6 is generating the executable but I'm also not married to the idea of using MD5. If there is a better way to verify that two executables are indeed the same then I'm all ears. Thanks in advance for your help!

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  • Are there any libraries for parsing "number expressions" like 1,2-9,33- in Java

    - by mihi
    Hi, I don't think it is hard, just tedious to write: Some small free (as in beer) library where I can put in a String like 1,2-9,33- and it can tell me whether a given number matches that expression. Just like most programs have in their print range dialogs. Special functions for matching odd or even numbers only, or matching every number that is 2 mod 5 (or something like that) would be nice, but not needed. The only operation I have to perform on this list is whether the range contains a given (nonnegative) integer value; more operations like max/min value (if they exist) or an iterator would be nice, of course. What would be needed that it does not occupy lots of RAM if anyone enters 1-10000000 but the only number I will ever query is 12345 :-) (To implement it, I would parse a list into several (min/max/value/mod) pairs, like 1,10,0,1 for 1-10 or 11,33,1,2 for 1-33odd, or 12,62,2,10 for 12-62/10 (i. e. 12, 22, 32, ..., 62) and then check each number for all the intervals. Open intervals by using Integer.MaxValue etc. If there are no libs, any ideas to do it better/more efficient?)

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  • Code Golf: Find the possible ways on a numpad

    - by ikar
    I was bored today at school and so I tried to amuse myself using my calculator and a "game" I've invented which isn't really a game but keeps the boringness away. Also some time has passed since the last real code-golf here, so I decided to create this one. Imagine a simplified numpad like you know it from your phone (I'll leave the 0 out for this code-golf as it kinda destroys all the fun) 1 2 3 4 5 6 7 8 9 Now the rules of the game were always: At the end every digit must have been visited exactly once You can start at any digit you want You can always move one digit up, down, left or right. You can't move diagonally! There a quite a lot of possible ways (or not; I haven't found out yet), here some trivial examples: > > v v < < > > | The output of the golf-program should look something like the above, I'll try to explain: Symbols: Go right < Go left ^ Go up v Go down | End of the way Example solutions: (Program output can either be the numbers pressed in the right order from beginning point to end, or an (ASCII) picture like above) 147852369 569874123 523698741 So if we speak out the example above it would be: Start at 1, move right to 2, move right to 3, go down to 6, go left to 5, go left to 4, go down to 7, go right to 8 then go right to 9 and we are finished! Now there are many different ways possible: You could as well start at 5 and go around it in a circle. So the task would be: Write a program that can compute (using brute-force or whatever) the possible solutions for the numpad problem described above. (Friendly rethorical question with smiley removed because it made some people think that this is homework)

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  • Excess errors on model from somewhere

    - by gmile
    I have a User model, and use an acts_as_authentic (from authlogic) on it. My User model have 3 validations on username and looks as following: User < ActiveRecord::Base acts_as_authentic validates_presence_of :username validates_length_of :username, :within => 4..40 validates_uniqueness_of :username end I'm writing a test to see my validations in action. Somehow, I get 2 errors instead of one when validating a uniqueness of a name. To see excess error, I do the following test: describe User do before(:each) do @user = Factory.build(:user) end it "should have a username longer then 3 symbols" do @user2 = Factory(:user) @user.username = @user2.username @user.save puts @user.errors.inspect end end I got 2 errors on username: @errors={"username"=>["has already been taken", "has already been taken"]}. Somehow the validation passes two times. I think authlogic causes that, but I don't have a clue on how to avoid that. Another case of problem is when I set username to nil. Somehow I get four validation errors instead of three: @errors={"username"=>["is too short (minimum is 3 characters)", "should use only letters, numbers, spaces, and .-_@ please.", "can't be blank", "is too short (minimum is 4 characters)"]} I think authlogic is one that causes this strange behaviour. But I can't even imagine on how to solve that. Any ideas?

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  • Silverlight ClientAccessPolicy issue...I think

    - by Terrence
    Fisrt of all I have my ClientAccessPolicy.xml file in the root of my website. If I access my website using the public domain name like this: h t t p://www.mydomain.com and then go to the page where my SL control is, I get the spinning % numbers up until about 98%, then it quits and my SL control does not appear on the page. If I access my website using the machine name (website is at datacenter, we have vpn setup) like this: h t t p://machinename and then go to the page where my SL control is everything works fine. this must be a ClientAccess Policy issue don't your think? Or what DO you thnik the issue is? Thanks in advance. Here is the contents of my ClientAccessPolicy.xml file: <?xml version="1.0" encoding="utf-8" ?> <access-policy> <cross-domain-access> <policy> <allow-from http-request-headers="*"> <domain uri="*" /> </allow-from> <grant-to> <resource path="/" include-subpaths="true" /> </grant-to> </policy> </cross-domain-access> </access-policy>

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  • increase number of photos from flickr using json

    - by Andrew Welch
    Hi this is my code: Is is possible to get more photos from flickr. What is the standard / default number? $(document).ready(function(){ $.getJSON("http://api.flickr.com/services/feeds/photos_public.gne?id=48719970@N07&lang=en-us&format=json&jsoncallback=?", function(data){ $.each(data.items, function(i, item){ var newurl = 'url(' + item.media.m + ')'; $("<div class='images'/>").css('background', newurl).css('backgroundPosition','top center').css('backgroundRepeat','no-repeat').appendTo("#images").wrap("<a target=\"_blank\ href='" + item.link + "'></a>"); }) $("#title").html(data.title); $("#description").html(data.description); $("#link").html("<a href='" + data.link + "' target=\"_blank\">Visit the Viget Inspiration Pool!</a>"); //Notice that the object here is "data" because that information sits outside of "items" in the JSON feed $('.jcycleimagecarousel').cycle({ fx: 'fade', speed: 300, timeout: 3000, next: '#next', prev: '#prev', pause: 1, random: 1 }); }); });

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  • How do I create a Status Icon / System Tray Icon with custom text and transparent background using P

    - by Raugturi
    Here is the code that I have so far to define the icon: icon_bg = gtk.gdk.pixbuf_new_from_file('gmail.png') w, h = icon_bg.get_width(), icon_bg.get_height() cmap = gtk.gdk.Colormap(gtk.gdk.visual_get_system(), False) drawable = gtk.gdk.Pixmap(None, w, h, 24) drawable.set_colormap = cmap gc = drawable.new_gc() drawable.draw_pixbuf(gc, icon_bg, 0, 0, 0, 0, w, h) drawn_icon = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, w, h) drawn_icon.get_from_drawable(drawable, cmap, 0, 0, 0, 0, w, h) icon = gtk.status_icon_new_from_pixbuf(drawn_icon) This works to get the png into the icon, but falls short in two areas. First, transparency is not working. If I use a 22x22 png with transparent background and the image centered, I end up with sections of other active icons showing up inside of mine, like this: http://i237.photobucket.com/albums/ff311/Raugturi/22x22_image_with_transparency.png The icon it choose to steal from is somewhat random. Sometimes it's part of the dropbox icon, others the NetworkManager Applet. If I instead use this code: icon_bg = gtk.gdk.pixbuf_new_from_file('gmail.png') w, h = icon_bg.get_width(), icon_bg.get_height() cmap = gtk.gdk.Colormap(gtk.gdk.visual_get_system(), False) drawable = gtk.gdk.Pixmap(None, w, h, 24) drawable.set_colormap = cmap gc = drawable.new_gc() drawable.draw_pixbuf(gc, icon_bg, 0, 0, 0, 0, w, h) drawn_icon = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, 22, 22) drawn_icon.get_from_drawable(drawable, cmap, 0, 0, 3, 6, w, h) icon = gtk.status_icon_new_from_pixbuf(drawn_icon) And an image that is only 16x11 with the transparent edges removed, what I end up with is this: Same URL but file is 16x11_image_positioned_in_middle.png So how do I end up with a transparent block like the 1st one that doesn't pull in stuff from other icons? As for the second problem, I need the ability to write on the image before converting it to the icon. I tried using draw_glyphs and it told me I should be using Pango layout/context instead. Unfortunately all the Pango tutorials I could find deal with actual windows, not the status icon. Is there a good tutorial out there for Pango that would apply to this issue (and also maybe have at least some explanation of how to tell it what font to use as all of them that I found seem to lack this and it won't write anything without it). Note: Sorry for the lack of actual images and only one working link, apparently this is a spam prevention feature due to my lack of reputation.

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  • what use does the javascript forEach method have (that map can't do)?

    - by JohnMerlino
    Hey all, The only difference I see in map and foreach is that map is returning an array and foreach is not. However, I don't even understand the last line of the foreach method "func.call(scope, this[i], i, this);". For example, isn't "this" and "scope" referring to same object and isn't this[i] and i referring to the current value in the loop? I noticed on another post someone said "Use forEach when you want to do something on the basis of each element of the list. You might be adding things to the page, for example. Essentially, it's great for when you want "side effects". I don't know what is meant by side effects. Array.prototype.map = function(fnc) { var a = new Array(this.length); for (var i = 0; i < this.length; i++) { a[i] = fnc(this[i]); } return a; } Array.prototype.forEach = function(func, scope) { scope = scope || this; for (var i = 0, l = this.length; i < l; i++) func.call(scope, this[i], i, this); } Finally, are there any real uses for these methods in javascript (since we aren't updating a database) other than to manipulate numbers like this: alert([1,2,3,4].map(function(x){ return x + 1})); //this is the only example I ever see of map in javascript. Thanks for any reply.

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  • PHP arrays - How to 1-dimensional array into nested multidimensional array?

    - by sombe
    When retrieving a hierarchical structure from MySQL (table with one ID column and one PARENT column signifying the hierarchical relationships), I map the result into an enumerated array as follows (for this example the numbers are arbitrary): Array ( [3] => Array ( [7] => Array () ), [7] => Array ( [8] => Array () ) ) Notice 3 is the parent of 7, and 7 is the parent of 8 (this could go on and on; and any parent could have multiple children). I wanted to shrink this array into a nested multidimensional array as follows: Array ( [3] => Array ( [7] => Array ( [8] => Array () ) ) ) That is, each NEW id is automatically assigned an empty array. Regardless, any ID's children will be pushed into their parent's array. Take a look at the following illustration for further clarification: This will probably result in a complicated recursive operation, since I always have to check whether a parent with any certain ID already exists (and if so, push the value into its array). Is there a built-in php function that can assist me with this? Do you have any idea as to how to go about constructing this? For what it's worth I'm using this to built a navigation bar in wordpress (which can contain categories, subcategories, posts... essentially anything).

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  • Wordpress inserting comments via wp_insert_comment()

    - by Cyber Junkie
    Hello all happy holidays! :) I'm trying to insert comments in my wordpress blog via the wp_insert_comment() function. It's for a plugin I'm trying to make. I have this code in my header for testing. It works every time I refresh the page. $agent = $_SERVER['HTTP_USER_AGENT']; $data = array( 'comment_post_ID' => 256, 'comment_author' => 'Dave', 'comment_author_email' => '[email protected]', 'comment_author_url' => 'http://www.someiste.com', 'comment_content' => 'Lorem ipsum dolor sit amet...', 'comment_author_IP' => '127.3.1.1', 'comment_agent' => $agent, 'comment_date' => date('Y-m-d H:i:s'), 'comment_date_gmt' => date('Y-m-d H:i:s'), 'comment_approved' => 1, ); $comment_id = wp_insert_comment($data); It successfully inserts comments into the database. The problem: Comments don't show via the Disqus comment system. I compared table rows and I noticed that user_agent differs. Normal comments use for example, Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv... and Disqus comments use Disqus/1.1(2.61):119598902 numbers are different for each comment. Does anyone know how to insert comments with wp_insert_comment() when Disqus is enabled?

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  • Fast way to manually mod a number

    - by Nikolai Mushegian
    I need to be able to calculate (a^b) % c for very large values of a and b (which individually are pushing limit and which cause overflow errors when you try to calculate a^b). For small enough numbers, using the identity (a^b)%c = (a%c)^b%c works, but if c is too large this doesn't really help. I wrote a loop to do the mod operation manually, one a at a time: private static long no_Overflow_Mod(ulong num_base, ulong num_exponent, ulong mod) { long answer = 1; for (int x = 0; x < num_exponent; x++) { answer = (answer * num_base) % mod; } return answer; } but this takes a very long time. Is there any simple and fast way to do this operation without actually having to take a to the power of b AND without using time-consuming loops? If all else fails, I can make a bool array to represent a huge data type and figure out how to do this with bitwise operators, but there has to be a better way.

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  • Saving animated GIFs using urllib.urlopen (image saved does not animate)

    - by wenbert
    I have Apache2 + Django + X-sendfile. My problem is that when I upload an animated GIF, it won't "animate" when I output through the browser. Here is my code to display the image located outside the public accessible directory. def raw(request,uuid): target = str(uuid).split('.')[:-1][0] image = Uploads.objects.get(uuid=target) path = image.path filepath = os.path.join(path,"%s.%s" % (image.uuid,image.ext)) response = HttpResponse(mimetype=mimetypes.guess_type(filepath)) response['Content-Disposition']='filename="%s"'\ %smart_str(image.filename) response["X-Sendfile"] = filepath response['Content-length'] = os.stat(filepath).st_size return response UPDATE It turns out that it works. My problem is when I try to upload an image via URL. It probably doesn't save the entire GIF? def handle_url_file(request): """ Open a file from a URL. Split the file to get the filename and extension. Generate a random uuid using rand1() Then save the file. Return the UUID when successful. """ try: file = urllib.urlopen(request.POST['url']) randname = rand1(settings.RANDOM_ID_LENGTH) newfilename = request.POST['url'].split('/')[-1] ext = str(newfilename.split('.')[-1]).lower() im = cStringIO.StringIO(file.read()) # constructs a StringIO holding the image img = Image.open(im) filehash = checkhash(im) image = Uploads.objects.get(filehash=filehash) uuid = image.uuid return "%s" % (uuid) except Uploads.DoesNotExist: img.save(os.path.join(settings.UPLOAD_DIRECTORY,(("%s.%s")%(randname,ext)))) del img filesize = os.stat(os.path.join(settings.UPLOAD_DIRECTORY,(("%s.%s")%(randname,ext)))).st_size upload = Uploads( ip = request.META['REMOTE_ADDR'], filename = newfilename, uuid = randname, ext = ext, path = settings.UPLOAD_DIRECTORY, views = 1, bandwidth = filesize, source = request.POST['url'], size = filesize, filehash = filehash, ) upload.save() #return uuid return "%s" % (upload.uuid) except IOError, e: raise e Any ideas? Thanks! Wenbert

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  • What is the fastest way for reading huge files in Delphi?

    - by dummzeuch
    My program needs to read chunks from a huge binary file with random access. I have got a list of offsets and lengths which may have several thousand entries. The user selects an entry and the program seeks to the offset and reads length bytes. The program internally uses a TMemoryStream to store and process the chunks read from the file. Reading the data is done via a TFileStream like this: FileStream.Position := Offset; MemoryStream.CopyFrom(FileStream, Size); This works fine but unfortunately it becomes increasingly slower as the files get larger. The file size starts at a few megabytes but frequently reaches several tens of gigabytes. The chunks read are around 100 kbytes in size. The file's content is only read by my program. It is the only program accessing the file at the time. Also the files are stored locally so this is not a network issue. I am using Delphi 2007 on a Windows XP box. What can I do to speed up this file access?

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  • Initialize Static Array of Structs in C

    - by russell_h
    I implementing a card game in C. There are lots of types of cards and each has a bunch of information, including some actions that will need to be individually scripted associated with it. Given a struct like this (and I'm not certain I have the syntax right for the function pointer) struct CARD { int value; int cost; // This is a pointer to a function that carries out actions unique // to this card int (*do_actions) (struct GAME_STATE *state, int choice1, int choice2); }; I would like to initialize a static array of these, one for each card. I'm guessing this would look something like this int do_card0(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } int do_card1(struct GAME_STATE *state, int choice1, int choice2) { // Operate on state here } extern static struct cardDefinitions[] = { {0, 1, do_card0}, {1, 3, do_card1} }; Will this work, and am I going about this the right way at all? I'm trying to avoid huge numbers of switch statements. Do I need to define the 'do_cardN' functions ahead of time, or is there some way to define them inline in the initialization of the struct (something like a lambda function in python)? I'll need read-only access to cardDefinitions from a different file - is 'extern static' correct for that? I know this is a lot of questions rolled into one but I'm really a bit vague about how to go about this. Thanks.

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