Search Results

Search found 5104 results on 205 pages for 'evolutionary algorithm'.

Page 171/205 | < Previous Page | 167 168 169 170 171 172 173 174 175 176 177 178  | Next Page >

• Disposing a Bitmap through its Finalizer

  - by devoured elysium

  I have a complex program in which I have to first create, then use wrappers around bitmaps and send them across a lot of different classes. The problem in the end is deciding which classes should dispose the bitmaps. Most of the time the end classes don't know if they can indeed dispose the bitmap as the same bitmap can be used in several places. Also, I can't just copy the bitmaps because this is a kind of resource intensive algorithm and doing it would be dead slow. I looked up on reflector for Image/Bitmap's implementations and they seem to use the Dispose Pattern. So, even if I don't call Dispose(), the CLR will eventually call it some other time. Is it too bad if I just let the bitmaps be as they are, and let the finalizer take care of them?

  Read the article

• How to create a 2D map of room by a few images/movie frames ?

  - by Nils

  I'd like to create a simple 2D map of a room by getting pictures (ceiling) of all directions (360° - e.g. movie frames), recognize the walls by edge detection, delete other unwanted objects, concat the images at the right position (cf. walls, panorama) and finally create the approximate 2D map (looking on it from above). Getting the scale would be another parameter, which might be useful. I have some own ideas at the moment, by using e.g. the Sobel algorithm, but it would be interesting if somebody out there knows some project or software (GPL,freeware prefered) doing this already, as I'm still looking for some examples, which might help me. Thanks.

  Read the article

• How do I determine darker or lighter color variant of a given color?

  - by Nidonocu

  Given a source color of any hue by the system or user, I'd like a simple algorithm I can use to work out a lighter or darker variants of the selected color. Similar to effects used on Windows Live Messenger for styling the user interface. Language is C# with .net 3.5. Responding to comment: Color format is (Alpha)RGB. With values as bytes or floats. Marking answer: For the context of my use (a few simple UI effects), the answer I'm marking as accepted is actually the most simple for this context. However, I've given up votes to the more complex and accurate answers too. Anyone doing more advanced color operations and finding this thread in future should definitely check those out. Thanks SO. :)

  Read the article

• Merging and splitting overlapping rectangles to produce non-overlapping ones

  - by uj

  I am looking for an algorithm as follows: Given a set of possibly overlapping rectangles (All of which are "not rotated", can be uniformly represented as (left,top,right,bottom) tuplets, etc...), it returns a minimal set of (non-rotated) non-overlapping rectangles, that occupy the same area. It seems simple enough at first glance, but prooves to be tricky (at least to be done efficiently). Are there some known methods for this/ideas/pointers? Methods for not necessarily minimal, but heuristicly small, sets, are interesting as well, so are methods that produce any valid output set at all.

  Read the article

• Sort an array via x86 Assembly (embedded in C++)?? Possible??

  - by Mark V.

  I am playing around with x86 assembly for the first time and I can't figure out how to sort an array (via insertion sort).. I understand the algorithm, but assembly is confusing me as I primarily use Java & C++. Heres all I have so far int ascending_sort( char arrayOfLetters[], int arraySize ) { char temp; __asm{ push eax push ebx push ecx push edx push esi push edi //// ??? pop edi pop esi pop edx pop ecx pop ebx pop eax } } Basically nothing :( Any ideas?? Thanks in advance.

  Read the article

• How can I use computer vision to find a shape in an image?

  - by Ryan

  I have a simple photograph that may or may not include a logo image. I'm trying to identify whether a picture includes the logo shape or not. The logo (rectangular shape with a few extra features) could be of various sizes and could have multiple occurrences. I'd like to use Computer Vision techniques to identify the location of these logo occurrences. Can someone point me in the right direction (algorithm, technique?) that can be used to achieve this goal? I'm quite a novice to Computer Vision so any direction would be very appreciative. Thanks!

  Read the article

• Security issues in accepting passwords vs auto generating the password

  - by Vivekanand Poojari

  Hi, I am developing a console application. This application generates a self signed certificate and installs it in the current machine's certificate store. The steps invlolved are :- Generate a certificate Create a pfx file Install the pfx file For these steps i would need a password for protecting the private key and the pfx file. However these passwords are used only during the execution of the exe. Should I auto generate a password using some random number generation algorithm or accept the password as input from the user? What are the security issues involved in both the scenarios ? Thanks Vivekanand

  Read the article

• Fitting place names into map shapes

  - by Old Man

  I'm drawing shapes using GDI+ using a list of lat/lon floats, and I need to place the name of the place within the borders of the polygon. Simply centering the text in the bounding rectangle doesn't work for irregular shapes. I have the text and the font so I can get the size of the rectangle that the text will need to fit in, but at that point I'm stuck. This seems like a common problem that all mapping software solves, as well as the kind of thing you would find in an algorithm or computer graphics textbook. So, given a list of floats for a polygon and a rectangle, is there a way to get the best possible point to place the text, using: 1) GDI+; 2) SQL Server Geospatial; or 3) c# code (or c, pseudocode, etc)

  Read the article

• RBF neural networks

  - by Infinity

  Hello guys! I would like to apply RBF neural networks to teach my system. I have a system with an input: | 1 2 3 4 5 6 ... 32 | 33 | | 1000 0001 0010 0100 1000 1000 ... 0100 | 0 0 1 | You have to read this without the "|" character. I just wanted you to see that the last three elements in the input are staying together. The result have to be a number between 1-32, which has the value "1000" in the input. In my training set I will always have a result for an array of this kind. What kind of functions can I use for the teaching algorithm? Can you point me please to the right way? If you can't understand my description please don't hesitate to ask about it. Thank you guys for your help!

  Read the article

• Controlling new features in Spring/Apache tomcat

  - by HeretoLearn

  Is there a good way to manage roll out of new software in Spring/Tomcat configuration. The problem I am trying to address is being able to rollback newly deployed software provided there are no hard dependencies on other moving pieces. For example changed the guts of an algorithm and now want to deploy the new software with the new change off by default and then turning it on on one of the web servers. An obvious way is to build a session object which has a map of key-value pairs(property,bool) which is populated from a db on a session startup and then the value is persisted for that session. This is so that if the value is reverted back existing sessions which started with the original value retain the original value and giving application consistency. Is there a more obvious inbuilt mechanism to do this?

  Read the article

• How to compare two char* variables

  - by davit-datuashvili

  Suppose we have the following method (it is in c code): const char *bitap_search(const char *text, const char *pattern) My question is how can I compare text and pattern if they are char? This method is like a substring problem but I am confused a bit can I write in term of char such code? if (text[i]==pattern[i])? look i am interesting at this algorithm in java http://en.wikipedia.org/wiki/Bitap_algorithm how implement this in java? R = malloc((k+1) * sizeof *R); and please help me to translate this code in java

  Read the article

• Overhead of serving pages - JSPs vs. PHP vs. ASPXs vs. C

  - by John Shedletsky

  I am interested in writing my own internet ad server. I want to serve billions of impressions with as little hardware possible. Which server-side technologies are best suited for this task? I am asking about the relative overhead of serving my ad pages as either pages rendered by PHP, or Java, or .net, or coding Http responses directly in C and writing some multi-socket IO monster to serve requests (I assume this one wins, but if my assumption is wrong, that would actually be most interesting). Obviously all the most efficient optimizations are done at the algorithm level, but I figure there has got to be some speed differences at the end of the day that makes one method of serving ads better than another. How much overhead does something like apache or IIS introduce? There's got to be a ton of extra junk in there I don't need. At some point I guess this is more a question of which platform/language combo is best suited - please excuse the in-adroitly posed question, hopefully you understand what I am trying to get at.

  Read the article

• How can you stream results as json string downloads?

  - by midas06

  I'm interested in presenting results faster in my mobile app. Is it possible to stream results out as the string downloads? I'm thinking about implementing an IObservable to push out the results as they are downloaded, but I don't know what algorithm to use to properly piece together the data which could be incomplete at any given point. Hope that was clear enough. CLARIFICATION: Guess it wasn't clear enough. My issue is the string downloaded is quite long. It can often take 15-20 seconds or more to download. I want to reflect changes faster to my user, so I would like to use reactive extensions to pump out entities as soon as a complete one is received. My issue is I dont know how to build the parser that can pick out complete entities from an incomplete response string.

  Read the article

• Best .Net/C# book for an interview

  - by DrunkenBeard

  Hi, I'm having an interview for an internship in the coming days and would like to know if there are any books that are particulary suited for preparing interviews. The interview is not particulary hard, just some questions about .Net and C# plus an algorithm to code. I tried C# in a Nutshell but it goes in too much detail for what I want to achieve. I'm more looking for a good yet small book that explains the important concepts of the .Net framework and C#, I already know the details, just want formal explanations so I'm confident when answering. Thanks :)

  Read the article

• Image analysis on the iPhone

  - by user362808

  Hi, guys! Hopefully a quick one. Working on a devious little algorithm that'll automatically scan a user's iPhone for a photo of some emotional poignance (e.g. go back in time a ways, look for one of a group of photos that are proximally timestamped, etc.). Need a quick-and-dirty way of picking out a photo containing two people in close proximity to each other. I know that the OpenCV Python lib [for image processing] works on the iPhone, I'm just curious whether it's actually the best way of doing this (from scratch or otherwise). Cheers!

  Read the article

• Most optimal way to detect if black (or any color pixels) exist in an image file?

  - by Zando

  What's the best and most flexible algorithm to detect any black (or colored pixel) in a given image file? Say I'm given an image file that could, say, have a blue background. And any non blue pixel, including a white pixel, is counted as a "mark". The function returns true if there are X number of pixels that deviate from each other at a certain threshold. I thought it'd be fastest to just simply iterate through every pixel and see if its color matches the last. But if it's the case that pixel (0,0) is deviant, and every other pixel is the same color (and I want to allow at least a couple deviated pixels before considering an image to be "marked), this won't work or be terribly efficient.

  Read the article

• What's the fastest way to search a very long list of words for a match in actionscript 3?

  - by Nuthman

  So I have a list of words (the entire English dictionary). For a word matching game, when a player moves a piece I need to check the entire dictionary to see if the the word that the player made exists in the dictionary. I need to do this as quickly as possible. simply iterating through the dictionary is way too slow. What is the quickest algorithm in AS3 to search a long list like this for a match, and what datatype should I use? (ie array, object, Dictionary etc)

  Read the article

• Will a source-removal sort always return a maximal cycle?

  - by Jason Baker

  I wrote a source-removal algorithm to sort some dependencies between tables in our database, and it turns out we have a cycle. For simplicity, let's say we have tables A, B, C, and D. The edges are like this: (A, B) (B, A) (B, C) (C, D) (D, A) As you can see, there are two cycles here. One is between A and B and another is between all four of them. Will this type of sort always choke on the largest cycle? Or is that not necessarily the case?

  Read the article

• Returning a list in this recursive coi function in python.

  - by Nate

  Hello. I'm having trouble getting my list to return in my code. Instead of returning the list, it keeps returning None, but if I replace the return with print in the elif statement, it prints the list just fine. How can I repair this? def makeChange2(amount, coinDenomination, listofcoins = None): #makes a list of coins from an amount given by using a greedy algorithm coinDenomination.sort() #reverse the list to make the largest position 0 at all times coinDenomination.reverse() #assigns list if listofcoins is None: listofcoins = [] if amount >= coinDenomination[0]: listofcoins = listofcoins + [coinDenomination[0]] makeChange2((amount - coinDenomination[0]), coinDenomination, listofcoins) elif amount == 0: return listofcoins else: makeChange2(amount, coinDenomination[1:], listofcoins)

  Read the article

• how to get the value of checksum in php header

  - by sumit

  I have a header in php which contains a link like <?php header("Location: "."https://abc.com/ppp/purchase.do?version=3.0&". "merchant_id=<23255>&merchant_site_id<21312>&total_amount=<69.99>&". "currency=<USD>&item_name_1=<incidentsupporttier1>&item_amount_1=<1>&". "time_stamp=<2010-06-14.14:34:33>&**checksum=<calculated_checksum>**"); ?> when i run this page the value of checksum is calculated and the link is opened now how checksum is calculated? calculated_checksum=md5(abc); md5 is an algorithm which calculates the value of checksum based on certain values inside the bracket. now i want to know how can i pass the value of checksum in the header url

  Read the article

• How to check that a regular expression fall into infty loop or not?

  - by Sorush Rabiee

  I'm trying to learn and hopefully use regular expression with Qt. I found that some patterns cause handler to fall into loop. for example searching \b\b in a text, never will terminate. and number of these expressions is infinite (\b\b\b,\b\b\b\b and so on). I'd like to determine and control all invalid expressions. Is there an algorithm to distinguish valid and invalid expressions? If not, how can I prevent my program from falling into an infinite loop?

  Read the article

• Project Euler: problem 8

  - by Marijus

  n = # some ridiculously large number, omitted N = [int(i) for i in str(n)] maxProduct = 0 for i in range(0,len(N)-4): newProduct = 1 is_cons = 0 for j in range(i,i+4): if N[j] == N[j+1] - 1: is_cons += 1 if is_cons == 5: for j in range(i,i+5): newProduct *= N[j] if newProduct > maxProduct: maxProduct = newProduct print maxProduct I've been working on this problem for hours now and I can't get this to work. I've tried doing this algorithm on paper and it works just fine.. Could you give me hints what's wrong ?

  Read the article

• Best way to search a point across several polygons

  - by user1474341

  I have a requirement whereby I need to match a given point (lat,lon) against several polygons to decide if there is a match. The easiest way would be to iterative over each polygon and apply the point-in-polygon check algorithm, but that is prohibitively expensive. The next optimization that I did was to define a bounding rectangle for each polygon (upper bound, lower bound) and iteratively check the point against the bounding box (fewer comparisons as against checking all the points in the polygon). Is there any other optimization possible? Would a spatial index on the bound rectangle points or a geohash help ? Any guidance would be greatly appreciated. Thanks!

  Read the article

• 16 millisecond quantization when sending/receivingtcp packets

  - by MKZ

  Hi, I have a C++ application running on windows xp 32 system sending and receiving short tcp/ip packets. Measuring (accurately) the arrival time I see a quantization of the arrival time to 16 millisecond time units. (Meaning all packets arriving are at (16 )xN milliseconds separated from each other) To avoid packet aggregation I tried to disable the NAGLE algorithm by setting the IPPROTO_TCP option to TCP_NODELAY in the socket variables but it did not help I suspect that the problem is related to the windows schedular which also have a 16 millisecond clock.. Any idea of a solution to this problem ? Thanks

  Read the article

• how to create english language dictionary application with python (django)?

  - by sintaloo

  Hi All, I would like to create an online dictionary application by using python (or with django). It will be similar to http://dictionary.reference.com/. My question is (1) Are there any existing open source python package or modules or application which implements this functionality that I can use or study from? (2) If the answer to the first question is NO. which algorithm should I follow to create such web application? Can I simply use the python built-in dictionary object for this job? so that the dictionary object's key will be the english word and the value will be the explanation. is this OK in term of performance? OR Do I have to create my own Tree Object to speed up the search? or any existing package which handles this job properly? Thank you very much.

  Read the article

< Previous Page | 167 168 169 170 171 172 173 174 175 176 177 178  | Next Page >