Search Results

Search found 3365 results on 135 pages for 'math'.

Page 104/135 | < Previous Page | 100 101 102 103 104 105 106 107 108 109 110 111  | Next Page >

• Is my code really not unit-testable?

  - by John

  A lot of code in a current project is directly related to displaying things using a 3rd-party 3D rendering engine. As such, it's easy to say "this is a special case, you can't unit test it". But I wonder if this is a valid excuse... it's easy to think "I am special" but rarely actually the case. Are there types of code which are genuinely not suited for unit-testing? By suitable, I mean "without it taking longer to figure out how to write the test than is worth the effort"... dealing with a ton of 3D math/rendering it could take a lot of work to prove the output of a function is correct compared with just looking at the rendered graphics.

  Read the article

• Newbie programmer looking for a fun, small project (pref. C++/Python)

  - by Francisco P.

  Hello everyone, I have some experience in Scheme and C++ (read: a semester of each) I know the very basics of Python (used it for physics simulations with the Visual Python module). Can you recommend me some fun and small (i.e. don't take much time) projects on either Python or C++? I have no real preferences, just that it is fun :P Thanks for your time! PS: I've tried projecteuler and python challenge. Euler is good, but more about math than coding, and py challenge just didn't work for me.

  Read the article

• How to column-ify an output from a certain program?

  - by mbaitoff

  I have a program that generates and outputs a sequence of simple sample math homework tasks, like: 1 + 1 = ... 3 + 3 = ... 2 + 5 = ... 3 + 7 = ... 4 + 2 = ... a sequence can be quite long, and I'd like to save space when this sequence is printed by converting it as follows: 1 + 1 = ... 3 + 7 = ... 3 + 3 = ... 4 + 2 = ... 2 + 5 = ... that is, wrapping the lines into the two or more columns. I was expecting the column linux utility to do the job using the -c N option witn N=2, however, it still outputs the lines in one column whatever the N is. How would I do the column-ifying of the sequence of lines?

  Read the article

• Parallel Processing Simulation in Javascript

  - by le_havre

  Hello, I'm new to JavaScript so forgive me for being a n00b. When there's intensive calculation required, it more than likely involves loops that are recursive or otherwise. Sometimes this may mean having am recursive loop that runs four functions and maybe each of those functions walks the entire DOM tree, read positions and do some math for collision detection or whatever. While the first function is walking the DOM tree, the next one will have to wait its for the first one to finish, and so forth. Instead of doing this, why not launch those loops-within-loops separately, outside the programs, and act on their calculations in another loop that runs slower because it isn't doing those calculations itself? Retarded or clever? Thanks in advance!

  Read the article

• Accommodating null values in a list?

  - by h259bws

  Hi, I'm new to Java and Groovy and am running into trouble with the following Groovy script. I created this whittled down version of a larger script to facilitate debugging. The script is iterating through a list trying to calc a running total of the values of all objects in the list. Some or all of these objects' values may be null. Script import org.apache.commons.lang.math.NumberUtils class Field { def name def value } def fields = [ new Field(name:'Annuities %', value:75), new Field(name:'Other %', value:null), ] //def totalFunding = fields.inject(0) {int total, Field myField - // total + NumberUtils.toInt(myField.value,0) as Integer def totalFunding = fields.inject(0) {int total, Field myField - total + myField?.value as Integer } It gets this error: Exception thrown: java.lang.NullPointerException java.lang.NullPointerException at Script3$_run_closure1.doCall(Script3:15) at Script3.run(Script3:14) What is the correct way to accomodate null values? Thanks, Betsy

  Read the article

• Calculate Spearman's Rank Correlation Coefficient

  - by Arvigeus

  I'm trying to calculate correlations using this method. However, when I do the math by hand, I get one result, and when I do it with R - cor(dt, use="complete.obs", method="spearman") - I get totally different thing. Example data below: --------------------------------- AnswerPosID.1007 AnswerPosID.1008 --------------------------------- 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 2 1 1 1 1 1 1 1 1 2 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 --------------------------------- Manual result: 0.799777530589544; R cor: -0.07142857

  Read the article

• Can't set element ID in JavaScript, it's always undefined

  - by Dylaan Alith

  Hi, I want to have a function that generates ID's on the fly for a given jquery object, if it doesn't have one already. These ID's should then be used in future requests. I came up with the code below, but it doesn't work. The ID's are never set. The commented out alert statement below always return undefined. I always pass code like $(this) or $(options.el) as a parameter to substitute 'el'. Initially, the elements do not have explicitly ID set in HTML. Any help would be appreciated, here's the code: getElementId: function(el) { if(undefined == el.attr('id')) { el.attr('id',"anim-"+Math.random().toString().substr(2)); } // alert(el.attr('id')); return el.attr('id'); },

  Read the article

• How do I generate a random time interval and add it to a mysql datetime using php?

  - by KeenLearner

  I have many rows in mysql table with datetime's in the format of: 2008-12-08 04:16:51 etc I'd like to generate a random time interval of anywhere between 30 seconds, and 3 days and add them to the time above. a) how do I generate a random time between 30 and 3 days? b) how do I add this time to the date time format above? I imagine i need to do a loop to pull out all the info, do the math in php, and then update the row... Any ideas?

  Read the article

• How do I indicate that a class doesn't support certain operators?

  - by romeovs

  I'm writing a class that represents an ordinal scale, but has no logical zero-point (eg time). This scale should permit addition and substraction (operator+, operator+=, ...) but not multiplication. Yet, I always felt it to be a good practice that when one overloads one operator of a certain group (in this case the math operators), one should also overload all the others that belong to that group. In this case that would mean I should need to overload the multiplication and division operators also, because if a user can use A+B he would probable expect to be able the other operators. Is there a method that I can use to throw an error for this at compiler time? The easiest method would be just no to overload the operators operator*, ... yet it would seem appropriate to add a bit more explaination than operator* is not know for class "time". Or is this something that I really should not care about (RTFM user)?

  Read the article

• Amazon EC2 multiple servers share session state

  - by Theofanis Pantelides

  Hi everyone, I have a bunch of EC2 servers that are load balanced. Some of the servers are not sharing session, and users keep getting logged in and out. How can I make all the server share the one session, possibly even using a partitionresolver solution public class PartitionResolver : System.Web.IPartitionResolver { private String[] partitions; public void Initialize() { // create the partition connection string table // web1, web2 partitions = new String[] { "192.168.1.1" }; } public String ResolvePartition(Object key) { String oHost = System.Web.HttpContext.Current.Request.Url.Host.ToLower().Trim(); if (oHost.StartsWith("10.0.0") || oHost.Equals("localhost")) return "tcpip=127.0.0.1:42424"; String sid = (String)key; // hash the incoming session ID into // one of the available partitions Int32 partitionID = Math.Abs(sid.GetHashCode()) % partitions.Length; return ("tcpip=" + partitions[partitionID] + ":42424"); } } -theo

  Read the article

• Run java with highest security setting

  - by Ankiov Spetsnaz

  I'm currently writing an in house coding challenge web application and I am wondering if there is any other security precaution I would need to have other than below java option at runtime. java -Djava.security.manager=default Basically, challenges would be more of single threaded math and algorithm focused. So I would need to enable basic data structure objects and disable any file, sockets, threading or any thing that might be not so important. Based on my quick search turning on security manager as above seems to be a solution but since this is a security related I would like to be sure before it goes alive. Is there anything else I could do more?

  Read the article

• android, find the nearest location without going through all the locations

  - by Marwan

  I am building a taxi dispatching app first: I need the passenger app to show the nearest taxis, now I know how to do that in code but in my way I have to go through all the taxis locations(in database on server) and calculate the distance from the passenger location and get the lowest ones - I don't want to do this because there will be a lot of taxis and going through all of them and making some math is kind of pain on the server- is there a way to get the nearest ones without going through all of them? second: what the best database to use - first, should it be sql or non-sql - I need a very robust database, because there will be a lot of updates (I mean the passengers locations added then deleted when arriving to destination && the taxis location changes frequently) finally: I will use RubyOnRails to do the server side and json as data transfer format, do you have a recommendation to me on something better? Thanks

  Read the article

• Given a number N, find the number of ways to write it as a sum of two or more consecutive integers

  - by hilal

  Here is the problem (Given a number N, find the number of ways to write it as a sum of two or more consecutive integers) and example 15 = 7+8, 1+2+3+4+5, 4+5+6 I solved with math like that : a + (a + 1) + (a + 2) + (a + 3) + ... + (a + k) = N (k + 1)*a + (1 + 2 + 3 + ... + k) = N (k + 1)a + k(k+1)/2 = N (k + 1)*(2*a + k)/2 = N Then check that if N divisible by (k+1) and (2*a+k) then I can find answer in O(N) time Here is my question how can you solve this by dynamic-programming ? and what is the complexity (O) ? P.S : excuse me, if it is a duplicate question. I searched but I can find

  Read the article

• detecting returned errors with $.post

  - by sova

  I'm using $.post to send a query to a JSP which returns some awesome data for me. If the query is malformed, however, the page returns with "error on page" and an HTTP Status of 500 Internal Server Error in jQuery, how can I detect this error so I can tell the user of the failure? runQuery : function () { $.post( admin_stats.runQueryURL, { buster : Math.random, statsQuery: admin_stats.getQuery(), jsp: 'admin_statsQuery' }, admin_stats.handleStatsQuery, "html" ); the returned data is an HTML table which is sufficient for this project at the moment. Also: totally open to criticism if this is ugly or not the way I should be doing things =)

  Read the article

• Generating a beveled edge for a 2D polygon

  - by Metaphile

  I'm trying to programmatically generate beveled edges for geometric polygons. For example, given an array of 4 vertices defining a square, I want to generate something like this. But computing the vertices of the inner shape is baffling me. Simply creating a copy of the original shape and then scaling it down will not produce the desired result most of the time. My algorithm so far involves analyzing adjacent edges (triples of vertices; e.g., the bottom-left, top-left, and top-right vertices of a square). From there, I need to find the angle between them, and then create a vertex somewhere along that angle, depending on how deep I want the bevel to be. And because I don't have much of a math background, that's where I'm stuck. How do I find that center angle? Or is there a much simpler way of attacking this problem?

  Read the article

• I love programming but i also want to learn hardware. [closed]

  - by user167082

  I like programming so much, i did it since i was 10, and i believe that studying computer science will make a lot of money as well as i love it. However I also want to learn hardware. I don't only want to do programming all the time without knowing the architecture of device that i program. I asked my teacher, and she said that if I get into computer science, i won't learn anything about hardware, is it true?(She graduated from u-dub) In the other hand, my math teacher told me to get into electrical engineering, since it also contain programming. The thing is that i want to emphasize my study to programming while learning some about hardware. What is major that suits me the best? Can i take some hardware courses if I get into computer science major? Thanks a lot.

  Read the article

• how does a research topic fit into a program?

  - by Asj

  My project is supposed to be about creating a program to help put a math test online. The program should generate questions that vary on each run of the test, and it should grade the test after someone takes it. (I found out recently that there's a system that can do some of the tasks already, but I don't think many people know how to use it) What type of research could be involved? I need to find a research article that relates to my project, and I'm having a lot of trouble figuring out what type of subject to look for.

  Read the article

• Should I learn Haskell or F# if I already know OCaml?

  - by Unknown

  I am wondering if I should continue to learn OCaml or switch to F# or Haskell. Here are the criteria I am most interested in: Longevity Which language will last longer? I don't want to learn something that might be abandoned in a couple years by users and developers. Will Inria, Microsoft, University of Glasgow continue to support their respective compilers for the long run? Practicality Articles like this make me afraid to use Haskell. A hash table is the best structure for fast retrieval. Haskell proponents in there suggest using Data.Map which is a binary tree. I don't like being tied to a bulky .NET framework unless the benefits are large. I want to be able to develop more than just parsers and math programs. Well Designed I like my languages to be consistent. Please support your opinion with logical arguments and citations from articles. Thank you.

  Read the article

• Intermittent/staggered loading of an object

  - by cammy

  Hi guys, I've just recently tried my hand at actionscript 3 and have come across a road block. How do I go about rendering the cubes (cube1) intermittently, ie. staggered loading. I need the cubes to load a split second from each other. Below is a snippet of what I have so far: var rows:int = 5; var cols:int = 3; var spacery:int = 100; var spacerx:int = 120; var box_count:int = 8; for(var i:int; i < box_count; i++) { cube1 = new Cube(ml,100,10,80,1,1,1); cube1.y = ((i % rows)) * (cube1.x + spacery); cube1.x = Math.floor(i/rows) * (cube1.x +spacerx); cube1.z = 0; bigBox.addChild(cube1); }

  Read the article

• How to retrieve the location of a control on the view?

  - by amok

  I have a button on a view, I want to add another button next to it when the first button is touched. Therefore I need it's top left corner to do the math. Here's what is puzzling me greatly: // this code is executed when the button is pressed NSLog(@"X:%f",moreButton.frame.origin.x); that returns on the first and second click the followings: 2010-04-24 22:58:25.883 iPad PopOver[8095:40b] X:-1.999002 2010-04-24 22:58:25.884 iPad PopOver[8095:40b] Y:0.000000 why and how can I get the x,y of an existing button on the view? (button created via IB) Thanks! mE ps: I have looked at similar posts and my code looks fine but I keep getting zeros (it's an ipad app if matters in any way)

  Read the article

• What's the silliest programming mistake you've ever done? [closed]

  - by bgo

  Despite not being a professional programmer, i use python or c to accomplish simple tasks. Once I needed a nasty equation to use with various data for physics lab. I thought that it would take a few hours if i used some mechanic calculator. Then i've written a python script to make things easier but something was wrong. After finding my mistakes one of which was forgetting to put ":", i realized that it had already took 2-3 hours, not to mention inventing satanic arithmetic techniques since i thought the errors was caused by my math :) Sometimes when you don't see it, you don't see it! Now i can find the syntax errors without thinking for a moment :) Any similar annoying mistakes that you've experienced?

  Read the article

• jquery ajax form function(data)

  - by RussP

  Can some one please tell me where I have gone wrong. What ever I do I get the answer "no" JQuery to send data to php query $j.post("logincheck.php",{ username:$j('#username').attr('value'), password:$j('#password').attr('value'), rand:Math.random() } , function(data) { if(data=='yes') {alert('yes');} else {alert('no');} } ); Here is the php query if(isset($_POST['username'])): $username = $_POST['username']; $password = $_POST['password']; $posts = mysql_query("SELECT * FROM users WHERE username='$username'"); $no_rows = mysql_num_rows($posts ); while($row = mysql_fetch_array($posts)): print 'yes'; endwhile; else: print 'no'; //header('location: index.php'); endif; endif; Thank in adance

  Read the article

• Application Servers(java) : Should adding RAM to server depend on each domain's -Xmx value?

  - by ring bearer

  We have Glassfish application server running in Linux servers. Each Glassfish installation hosts 3 domains. Each domain has a JVM configuration such as -Xms 1GB and -XmX 2GB. That means if all these three domains are running at max memory, server should be able to allocate total 6GB to the JVMs With that math,each of our server has 8GB RAM (2 GB Buffer) First of all - is this a good approach? I did not think so, because when we analyzed memory utilization on this server over past few months, it was only up to 1GB; Now there are requests to add an additional domain to these servers - does that mean to add additional 2 GB RAM just to be safe or based on trend, continue with whatever memory the server has?

  Read the article

• algorithmes with no executable example code

  - by gcc

  [link] http://stackoverflow.com/questions/2932016/parsing-of-mathematical-expressions (problem has been told before) ** program is to create the infix tree for the given math expression.** if the expression is given completely paranthesized then the out put is fine but when there are no paranthesis or some part paranthesized then the out put is wrong. cant get the idea how to solve. my problem is told above. I have some algorithm to solve my problem, but I have no simple code which will be guide for me. Can anyone give me simple code (not working code) so that I will try working to understand.(for a 3 hours ,I have been searching and reading some text to understand algorithm which is told above.Actually,there is no example code investigating how it is working. Can anyone send me example which is written in c not other language.

  Read the article

• Using pow() for large number

  - by g4ur4v

  I am trying to solve a problem, a part of which requires me to calculate (2^n)%1000000007 , where n<=10^9. But my following code gives me output "0" even for input like n=99. Is there anyway other than having a loop which multilplies the output by 2 every time and finding the modulo every time (this is not I am looking for as this will be very slow for large numbers). #include<stdio.h> #include<math.h> #include<iostream> using namespace std; int main() { unsigned long long gaps,total; while(1) { cin>>gaps; total=(unsigned long long)powf(2,gaps)%1000000007; cout<<total<<endl; } }

  Read the article

< Previous Page | 100 101 102 103 104 105 106 107 108 109 110 111  | Next Page >