Search Results

Search found 11587 results on 464 pages for 'pseudo random numbers'.

Page 322/464 | < Previous Page | 318 319 320 321 322 323 324 325 326 327 328 329  | Next Page >

• (Python) algorithm to randomly select a key based on proportionality/weight

  - by LaundroMat

  Hi - I'm a bit at a loss as to how to find a clean algorithm for doing the following: Suppose I have a dict k: >>> k = {'A': 68, 'B': 62, 'C': 47, 'D': 16, 'E': 81} I now want to randomly select one of these keys, based on the 'weight' they have in the total (i.e. sum) amount of keys. >>> sum(k.values()) >>> 274 So that there's a >>> 68.0/274.0 >>> 0.24817518248175183 24.81% percent change that A is selected. How would you write an algorithm that takes care of this? In other words, that makes sure that on 10.000 random picks, A will be selected 2.481 times?

  Read the article

• Limiting object allocation over multiple threads

  - by John

  I have an application which retrieves and caches the results of a clients query. The client then requests different chunks of data and the application sends the relevant results and removes them from the cache. A new requirement for this application is that there needs to be a run-time configurable maximum number of results which may be cached. I've taken the naive approach and implemented this by using a counter under a lock which is incremented every time a result is cached and decremented whenever a result is removed from the cache. Unfortunately, this has drastically reduced the applications performance when processing a large number of concurrent requests. I have tried both a critical section lock and spin-lock; the performance improves a bit with a spin-lock, but is still unacceptably slow. Is there a better way to solve this problem which may improve performance? Right now I have a thread pool that services requests and each request is tied to a Request object which stores that cached results for that particular request. Here is a simplified pseudo code version of my current implementation: void ResultCallback( Result result, Request *request ) { lock totalResultsCached lock cachedLimit if( totalResultsCached + 1 > cachedLimit ) { unlock cachedLimit unlock totalResultsCached //cancel the request return; } ++totalResultsCached; unlock cachedLimit unlock totalResultsCached request.add(result) } void SendResults( int resultsToSend, Request *request ) { while ( resultsToSend > 0 ) { send(request.remove()) lock totalResultsCached --totalResultsCached unlock totalResultsCached --resultsToSend; } }

  Read the article

• How to prevent CAST errors on SSIS ?

  - by manitra

  Hello, The question Is it possible to ask SSIS to cast a value and return NULL in case the cast is not allowed instead of throwing an error ? My environment I'm using Visual Studio 2005 and Sql Server 2005 on Windows Server 2003. The general context Just in case you're curious, here is my use case. I have to store data coming from somewhere in a generic table (key/value structure with history) witch contains some sort of value that can be strings, numbers or dates. The structure is something like this : table Values { Id int, Date datetime, -- for history Key nvarchar(50) not null, Value nvarchar(50), DateValue datetime, NumberValue numeric(19,9) } I want to put the raw value in the Value column and try to put the same value in the DateValue column when i'm able to cast it to Datetime in the NumberValue column when i'm able to cast it to a number Those two typed columns would make all sort of aggregation and manipulation much easier and faster later. That's it, now you know why i'm asking this strange question. ============ Thanks in advance for your help.

  Read the article

• How can I avoid causing memory leaks in Firefox?

  - by mrdanimal

  It seems that there is a lot of information on memory leaks in IE and how web developers can avoid them, but I can't find much on avoiding leaks in FF. I've found lots of random tips on how end users can tweak their preferences, or tips for extension developers, but little on what I can do as a web developer to make sure my pages don't leak. Am I missing something? It seems lazy to just blame it on the user and say "you've got too many extensions". Or are the major patterns the same as in IE -- circular references and all that? Also, if anyone knows of any tools to troubleshoot leaks in FF, that would be great. I found this: https://addons.mozilla.org/en-US/firefox/addon/2490/ But it's apparently just for chrome and extension development.

  Read the article

• In Ruby, why does inspect() print out some kind of object id which is different from what object_id(

  - by Jian Lin

  When the p function is used to print out an object, it may give an ID, and it is different from what object_id() gives. What is the reason for the different numbers? >> a = Point.new => #<Point:0x4684abc> >> a.object_id => 36971870 >> a.__id__ => 36971870 >> "%X" % a.object_id => "234255E"

  Read the article

• Permutations in python 2.5.2

  - by flpgdt

  Hi, I have a list of numbers for input, e.g. 671.00 1,636.00 436.00 9,224.00 and I want to generate all possible sums with a way to id it for output, e.g.: 671.00 + 1,636.00 = 2,307.00 671.00 + 436.00 = 1,107.00 671.00 + 9,224.00 = 9,224.00 671.00 + 1,636.00 + 436.00 = 2,743.00 ... and I would like to do it in Python My current constrains are: a) I'm just learning python now (that's part of the idea) b) I will have to use Python 2.5.2 (no intertools) I think I have found a piece of code that may help: def all_perms(str): if len(str) <=1: yield str else: for perm in all_perms(str[1:]): for i in range(len(perm)+1): #nb str[0:1] works in both string and list contexts yield perm[:i] + str[0:1] + perm[i:] ( from these guys ) But I'm not sure how to use it in my propose. Could someone trow some tips and pieces of code of help? cheers, f.

  Read the article

• How can I access the int values of an object in an NSMutableArray?

  - by Daniel

  I try to access some values in a NSMutableArray I created, but I only get some numbers (address?) if I try to access them. I was able to initialize an array and can add and change objects with [myNSMutableArray addObject:[NSNumber numberWithInt:10]] and [myNSMutableArray replaceObjectAtIndex:0 withObject:[NSNumber numberWithInt:47] I also can print the value at index [0] with NSLog(@"%@", [myNSMutableArray objectAtIndex:0]); and I get 47 as expected. But how can I access the integer value of the object in the array so I can save it tomyIntValue?

  Read the article

• Django - User account with multiple identities

  - by Scott Willman

  Synopsis: Each User account has a UserProfile to hold extended info like phone numbers, addresses, etc. Then, a User account can have multiple Identities. There are multiple types of identities that hold different types of information. The structure would be like so: User |<-FK- UserProfile | |<-FK- IdentityType1 |<-FK- IdentityType1 |<-FK- IdentityType2 |<-FK- IdentityType3 (current) |<-FK- IdentityType3 |<-FK- IdentityType3 The User account can be connected to n number of Identities of different types but can only use one Identity at a time. Seemingly, the Django way would be to collect all of the connected identities (user.IdentityType1_set.select_related()) into a QuerySet and then check each one for some kind of 'current' field. Question: Can anyone think of a better way to select the 'current' marked Identity than doing three DB queries (one for each IdentityType)?

  Read the article

• When do Symfony's user attributes get written to session?

  - by Rob Wilkerson

  I have a Symfony app that populates the "widgets" of a portal application and I'm noticing something (that seems) odd. The portal app has iframes that make calls to the Symfony app. On each of those calls, a random user key is passed on the query string. The Symfony app stores that key its session using myUser->setAttribute(). If the incoming value is different from what it has in session, it overwrites the session value. In pseudo-code (and applying a synchronous nature for clarity even though it may not exist): # Widget request arrives with ?foo=bar if the user attribute 'foo' does not equal 'bar' overwrite the user attribute 'foo' with 'bar' end What I'm noticing is that, on a portal page with multiple widgets (read: multiple requests coming in more or less simultaneously) where the value needs to be overwritten, each request is trying to overwrite. Is this a timing problem? When I look at the log prints, I'd expect the first request that arrives to overwrite and subsequent requests to see that the user attribute they received matches what was just put into cache by the initial request. In this scenario, it could be that subsequent requests begin (and are checked) even before the first one--the one that should overwrite the cached value--has completely finished. Are session values not really available to subsequent requests until one request has completed entirely or could there be something else that I'm missing? Thanks.

  Read the article

• Is there a centralized list of country names that can be used for web drop down boxes (and validatio

  - by Thr4wn

  There are examples online with web select boxes that have a huge list of countries and that probably will be good enough for me to use. However, by Murphy's law, there's bound to be some random country that someone is from and isn't on my list (and probably someone else also ran into this and has updated their local list). Also, when new countries are added, I won't know about it. Basically, I feel it's better practice and a better smell if there is some centralized list of country names that I can use / trust. (also it could set/follow standards for exact namings "United St..." vs "USA" etc.) I would prefer a solution that isn't IIS specific if possible

  Read the article

• How to get REALLY fast python over a simple loop

  - by totallymike

  I'm working on a spoj problem, INTEST. The goal is to specify the number of test cases (n) and a divisor (k), then feed your program n numbers. The program will accept each number on a newline of stdin and after receiving the nth number, will tell you how many were divisible by k. The only challenge in this problem is getting your code to be FAST because it k can be anything up to 10^7 and the test cases can be as high as 10^9. I'm trying to write it in python and having trouble speeding it up. Any ideas? import sys first_in = raw_input() thing = first_in.split() n = int(thing[0]) k = int(thing[1]) total = 0 i = 0 for line in sys.stdin: t = int(line) if t % k == 0: total += 1 print total

  Read the article

• Pagination using Ajax in jquery Datatables

  - by kshtjsnghl

  I am using dataTables plugin for a table on a page I am working on. Its basically fetching rows through an ajax call and in this ajax call, I send the search params that the user selects and the page number required. I need the Next, Previous, First and Last buttons to also fire the same ajax call, but with different page numbers, as the back-end interceptor depends on the page number. This api call would return total no. of rows(say 1000) belonging for these search params and the rows with the page size( say 50). Is there any way, I can use data table to do this?

  Read the article

• How to force main Acivity to wait for subactivity in Android?

  - by rmaster

  hi, I am calling a subactivity from main activity. This subactivity should take few numbers from user (i'm using Edit text control to achieve this), save them to static variable in another class and terminate. I want main activity to wait for subactivity but both are just running simultaneously. Even doing sth like that doesn't help: Thread t = new Thread(new Runnable(){ public void run(){ Log.v("==================", "run "+new Date()); startActivityForResult(new Intent(ctx,myCustomSubactivity.class),1); } }); Log.v("==================", "calling run "+new Date()); t.start(); try { t.join(); } catch (InterruptedException e) {Log.v("==================", "can't join");} Log.v("==================", "back from activity "+new Date()); do you know how to force main activity to wait? Thread.wait() method is not supported in Android(program throws error).

  Read the article

• Hudson: where to download file and stop specific builds running ?

  - by Kim Jong Woo

  I have a file that is generated inside (hudson server) /var/lib/hudson/jobs/jobtitle/1/out.txt I need to fetch this file, but doing a GET request for http://myhudson:8090/job/jobtitle/1/out.txt doesn't actually locate the file. Basically, I have another box that will grab this file from the hudson server. This box will make the out.txt file available for download. Another challenge is the build number directories. How would I be able to use the hudson API to stop or delete the specific builds running ? I am forced to do iterate through all build numbers to send STOP or DELETE api call in php using wget to do the REST API call. This is not very efficient. for ($i=0; $i < 3000; $i++){ exec('wget -O /dev/null "http://myhudson:8090/job/' . 'jobtitle' . '/$i/stop"'); }

  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

• C++ integer floor function

  - by Thomas

  I want to implement greatest integer function. int x = 5/3; My question is with greater numbers could there be a loss of precision as 5/3 would produce a double? EDIT: Greatest integer function is integer less than or equal to X. Example: 4.5 = 4 4 = 4 3.2 = 3 3 = 3 What I want to know is 5/3 going to produce a double? Because if so I will have loss of precision when converting to int. Hope this makes sense. RE-EDIT: What OP calls 'greatest integer' most of us call 'floor'.

  Read the article

• Structure of open source project's repository

  - by hokkaido

  I'm in the beginning of starting a small open source project. When cloning the main repository one gets a complete build environment with all the libraries and all the tools needed to make an official installer file, with correct version numbers. I like the fact that anyone who wants to contribute can clone the repository and get started with anything they want. But I'm thinking this makes it to easy for Evil People to create malicious installers and release into the wild. How should it be structured? What do you recommend including in the repository, versus keeping on the build server only?

  Read the article

• Controling CRT memory initialization

  - by Ofek Shilon

  Occasionally you meet bugs that are reproducible only in release builds and/or only on some machines. A common (but by no means only) reason is uninitialized variables, that are subject to random behaviour. E.g, an uninitialized BOOL can be TRUE most of the time, on most machines, but randomly be initialized as FALSE. What I wish I would have is a systematic way of flushing out such bugs by modifying the behaviour of the CRT memory initialization. I'm well aware of the MS debug CRT magic numbers - at the very least I'd like to have a trigger to turn 0xCDCDCDCD (the pattern that initializes freshly allocated memory) to zeros. I suspect one would be able to easily smoke out nasty initialization pests this way, even in debug builds. Am I missing an available CRT hook (API, registry key, whatever) that enables this? Anyone has other ideas to get there?

  Read the article

• Forking Multiple Apps Under Python Subprocess

  - by noxtion

  Hello all. I have been looking through Google and SO for something that could help me solve this but I have run into a block. I am a bit new to Python but I am looking for a way to run multiple apps that will continuously run in the background. For example, I need 4 apps to start up with a param -appnum set to a different value. I would like to use python to count up and then start up a new app that will continue to run. I assumed I would use subprocess but I feel a bit overwhelmed by the documentation. I also plan to have the app print out sequences of numbers and would like to redirect this to a file. I noticed some of the SO questions talked about this, but I am a little confused on what to do. -Mike

  Read the article

• java for loop not working

  - by Steve

  I hope this isn't a stupid question but I have looked up every example I can find and it still seems like I have this code right and it still isn't working... I enter one number and it moves on to the next line of code instead of looping. I'm using this to fill an array with user input numbers. I appreciate any help, thanks. for(i=0; i<9; i++); { System.out.println ("Please enter a number:"); Num[i] = keyboard.nextDouble(); Sum += Num[i]; Product *= Num[i]; }

  Read the article

• User controlled html title tags

  - by zaf

  What are the best practices for allowing a user to maintain the html title tags of all the major pages of his/her site? One way could be to allow the mapping of URLs to some text. For example, we have an app with the following (most complex) url format: http://lang.example.com/searchpage.zaf?a=foo&b=bar&c=RANDOM There are several parts to this: Language sub domain Search page Static parameter 'a' (user may want this in the title) Dynamic and relevant parameter 'b' (user may want this in the title) Dynamic parameter 'c' which can be ignored Never done this before, so I'm asking how you would tackle this!

  Read the article

• Codeigniter: how should I restructure db schema?

  - by Kevin Brown

  I don't even know if that's the right term. May it be known that I'm a major novice! I have three tables: users, profiles, and survey. Each one has user_id as it's first field, (auto-increment for users), and they're all tied by a foreign key constraint, CASCADE on DELETE. Currently, for each user, let's say user_id 1, they have a corresponding db entry in the other tables. For profiles it lists all their information, and the survey table holds all their survey information. Now I must change things...darn scope creep. Users need the ability to have multiple survey results. I imagine that this would be similar to a comment table for a blog... My entire app runs around the idea that a single user is linked to a constraining profile and survey. How should I structure my db? How should I design my app's db so that a user can have multiple tests/profiles for the test? Please assist! Any advice, information and personal-knowledge is appreciated! Right now the only way I know how to accompany my client is to create a pseudo-user for each test (so unnecessary) and list them in a view table (called "your tests")-- these are obtained from the db by saying: where user_id=manager_id

  Read the article

• JavaCC: How can I specify which token(s) are expected in certain context?

  - by java.is.for.desktop

  Hello, everyone! I need to make JavaCC aware of a context (current parent token), and depending on that context, expect different token(s) to occur. Consider the following pseudo-code: TOKEN <abc> { "abc*" } // recognizes "abc", "abcd", "abcde", ... TOKEN <abcd> { "abcd*" } // recognizes "abcd", "abcde", "abcdef", ... TOKEN <element1> { "element1" "[" expectOnly(<abc>) "]" } TOKEN <element2> { "element2" "[" expectOnly(<abcd>) "]" } ... So when the generated parser is "inside" a token named "element1" and it encounter "abcdef" it recognizes it as <abc>, but when its "inside" a token named "element2" it recognizes the same string as <abcd>. element1 [ abcdef ] // aha! it can only be <abc> element2 [ abcdef ] // aha! it can only be <abcd> If I'm not wrong, it would behave similar to more complex DTD definitions of an XML file. So, how can one specify, in which "context" which token(s) are valid/expected? NOTE: It would be not enough for my real case to define a kind of "hierarchy" of tokens, so that "abcdef" is always first matched against <abcd> and than <abc>. I really need context-aware tokens.

  Read the article

• Collection was modified; enumeration operation may not execute

  - by Rita

  I have the below code. I am trying to remove the record and it is throwing Exception when it is removing the Record. "Collection was modified; enumeration operation may not execute." Any ideas on how to get rid of the message. Appreciate your time. //validClaimControlNo has valid ClaimControl Numbers. List<string> validClaimControlNo = new List<string>(); int count = 0; foreach (List<Field> f in records) { foreach (Field fe in f) { if (i == 0) if (!(validClaimControlNo.Contains(fe.Value))) { //if this claim is not in the Valid list, Remove that Record records.RemoveAt(count); } i++; } i = 0; count++; }

  Read the article

• Adding a UIView to a UITableViewCell via cell.contentView

  - by Robert Eisinger

  I have a class called GraphView that extends UIView that basically draws a small little line chart. I need one of these graphs at the top of each section in my UITableView. So I tried by creating a separate cell at the top of one of my sections and then on that cell I did: [cell.contentView addSubview:graphView]; [graphView release]; But when I scroll down, it's like the graph is glitchy and it shows up in random spots along the UITableView. Anyone have ideas or insight? Is there a better way to incorporate another UIView into the top of each section in my UITableView?

  Read the article

< Previous Page | 318 319 320 321 322 323 324 325 326 327 328 329  | Next Page >