Search Results

Search found 8262 results on 331 pages for 'optimization algorithm'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 127/331 | < Previous Page | 123 124 125 126 127 128 129 130 131 132 133 134  | Next Page >

  • Where can I learn more about datastructure tricky questions?

    - by Sandbox
    I am relatively new to programming (around 1 year programming C#-winforms). Also, I come from a non CS background (no formal degree) Recently, while being interviewed for a job, I was asked about implementing a queue using a stack. I fumbled and wan't able to answer the question. After, the interview I could do it(had to spend some time). I have learnt (and think that I know it well) basic algorithms in datastructures using the book Data Structures: A Pseudocode Approach with C - Richard F. Gilberg (Author) . I want to know about sites/ books which have such questions along with answers. I think this will allow me to develop my CS specific problem solving skills. Any help is appreciated. BOUNTY: I am looking at some blog/website with datastructure and algorithms Q&A.

    Read the article

  • How does Amazon's Statistically Improbable Phrases work?

    - by ??iu
    How does something like Statistically Improbable Phrases work? According to amazon: Amazon.com's Statistically Improbable Phrases, or "SIPs", are the most distinctive phrases in the text of books in the Search Inside!™ program. To identify SIPs, our computers scan the text of all books in the Search Inside! program. If they find a phrase that occurs a large number of times in a particular book relative to all Search Inside! books, that phrase is a SIP in that book. SIPs are not necessarily improbable within a particular book, but they are improbable relative to all books in Search Inside!. For example, most SIPs for a book on taxes are tax related. But because we display SIPs in order of their improbability score, the first SIPs will be on tax topics that this book mentions more often than other tax books. For works of fiction, SIPs tend to be distinctive word combinations that often hint at important plot elements. For instance, for Joel's first book, the SIPs are: leaky abstractions, antialiased text, own dog food, bug count, daily builds, bug database, software schedules One interesting complication is that these are phrases of either 2 or 3 words. This makes things a little more interesting because these phrases can overlap with or contain each other.

    Read the article

  • simple plot algorithm with autoscale

    - by adrin
    I need to implement a simple plotting component in C#(WPF to be more precise). What i have is a collection of data samples containing time (X axis) and a value (both double types). I have a drawing canvas of a fixed size (Width x Height) and a DrawLine method/function that can draw on it. The problem I am facing now is how do I draw the plot so that it is autoscaled? In other words how do I map the samples I have to actual pixels on my Width x Height canvas?

    Read the article

  • Revisions: algorithm and data structure

    - by SODA
    Hi, I need ideas for structuring and processing data with revisions. For example, I have a database of objects (e.g. cars). Each object has a number of properties, which can be arbitrary, so there's no a set schema to describe these objects. These objects are probably saved as key-value pairs. Now I need to change property of an object. I don't want to completely rewrite it - I want to be able to go back and see history of changes to these properties, that's why I want to add new property and keep the old one (so I guess a timestamp would do the job of telling which property is the latest). At the same time I want to be able to get info about any object in a snap, with only latest versions of each of the properties. Any ideas what would be the best approach? At least please point me in the right direction. Thanks!

    Read the article

  • Solving simultaneous equations

    - by Milo
    Here is my problem: Given x, y, z and ratio where z is known and ratio is known and is a float representing a relative value, I need to find x and y. I know that: x / y == ratio y - x == z What I'm trying to do is make my own scroll pane and I'm figuring out the scrollbar parameters. So for example, If the scrollbar must be able to scroll 100 values (z) and the thumb must consume 80% of the bar (ratio = 0.8) then x would be 400 and y would be 500. Thanks

    Read the article

  • Constructing colours for maximum contrast

    - by Martin
    I want to draw some items on screen, each item is in one of N sets. The number of sets changes all the time, so I need to calculate N different colours which are as different as possible (to make it easy to identify what is in which set). So, for example with N = 2 my results would be black and white. With three I guess I would get all red, all green, all blue. For all four, it's less obvious what the correct answer is, and this is where I'm having trouble.

    Read the article

  • Aligning music notes using String matching algorithms or Dynamic Programming

    - by Dolphin
    Hi I need to compare 2 sets of musical pieces (i.e. a playing-taken in MIDI format-note details extracted and saved in a database table, against sheet music-taken into XML format). When evaluating playing against sheet music (i.e.note details-pitch, duration, rhythm), note alignment needs to be done - to identify missed/extra/incorrect/swapped notes that from the reference (sheet music) notes. I have like 1800-2500 notes in one piece approx (can even be more-with polyphonic, right now I'm doing for monophonic). So will I have to have all these into an array? Will it be memory overloading or stack overflow? There are string matching algorithms like KMP, Boyce-Moore. But note alignment can also be done through Dynamic Programming. How can I use Dynamic Programming to approach this? What are the available algorithms? Is it about approximate string matching? Which approach is much productive? String matching algos like Boyce-Moore, or dynamic programming? How can I assess which is more effective? Greatly appreciate any insight or suggestions Thanks in advance

    Read the article

  • Non-Linear color interpolation?

    - by user146780
    If I have a straight line that mesures from 0 to 1, then I have colorA(255,0,0) at 0 on the line, then at 0.3 I have colorB(20,160,0) then at 1 on the line I have colorC(0,0,0). How could I find the color at 0.7? Thanks

    Read the article

  • Algorithm for sentence analysis and tokenization

    - by Andrea Nagar
    I need to analyze a document and compile statistics as to how many times each a sequence of words is used (so the analysis is not on single words but of batch of recurring words). I read that compression algorithms do something similar to what I want - creating dictionaries of blocks of text with a piece of information reporting its frequency. It should be something similar to http://www.codeproject.com/KB/recipes/Patterns.aspx Do you have anything written in C#?

    Read the article

  • Position elements without overlap

    - by eWolf
    I have a number of rectangular elements that I want to position in a 2D space. I calculate an ideal position for each element. Now my problem is that many elements overlap as very often the ideal positions are concentrated in one region. I want to avoid overlap as much as possible (doesn't have to be perfect, though). How can I do this? I've heard physics simulations are suitable for this - is that correct? And can anyone provide an example/tutorial? By the way: I'm using XNA, if you know any .NET library that does exactly this job - tell me!

    Read the article

  • Reverse engineering a bezier curve

    - by Martin
    Given a few sample points on a bézier curve, is it possible to work out the set of possible parameters of the curve? In my specific application there is a limited set of endpoints the curve may have, so I want to generate the set of possible curves, enumerate all of them and pick out all the ones which may end on a valid end point.

    Read the article

  • how to elegantly duplicate a graph (neural network)

    - by macias
    I have a graph (network) which consists of layers, which contains nodes (neurons). I would like to write a procedure to duplicate entire graph in most elegant way possible -- i.e. with minimal or no overhead added to the structure of the node or layer. Or yet in other words -- the procedure could be complex, but the complexity should not "leak" to structures. They should be no complex just because they are copyable. I wrote the code in C#, so far it looks like this: neuron has additional field -- copy_of which is pointer the the neuron which base copied from, this is my additional overhead neuron has parameterless method Clone() neuron has method Reconnect() -- which exchanges connection from "source" neuron (parameter) to "target" neuron (parameter) layer has parameterless method Clone() -- it simply call Clone() for all neurons network has parameterless method Clone() -- it calls Clone() for every layer and then it iterates over all neurons and creates mappings neuron=copy_of and then calls Reconnect to exchange all the "wiring" I hope my approach is clear. The question is -- is there more elegant method, I particularly don't like keeping extra pointer in neuron class just in case of being copied! I would like to gather the data in one point (network's Clone) and then dispose it completely (Clone method cannot have an argument though).

    Read the article

  • Is there a name for the technique of using base-2 numbers to encode a list of unique options?

    - by Lunatik
    Apologies for the rather vague nature of this question, I've never been taught programming and Google is rather useless to a self-help guy like me in this case as the key words are pretty ambiguous. I am writing a couple of functions that encode and decode a list of options into a Long so they can easily be passed around the application, you know this kind of thing: 1 - Apple 2 - Orange 4 - Banana 8 - Plum etc. In this case the number 11 would represent Apple, Orange & Plum. I've got it working but I see this used all the time so assume there is a common name for the technique, and no doubt all sorts of best practice and clever algorithms that are at the moment just out of my reach.

    Read the article

  • question about LSD radix sort

    - by davit-datuashvili
    hello i have following code public class LSD{ public static int R=1<<8; public static int bytesword=4; public static void radixLSD(int a[],int l,int r){ int aux[]=new int[a.length]; for (int d=bytesword-1;d>=0;d--){ int i, j; int count[]=new int[R+1]; for ( j=0;j<R;j++) count[j]=0; for (i=l;i<=r;i++) count[digit(a[i],d)+1]++; for (j=1;j<R;j++) count[j]+=count[j-1]; for (i=l;i<=r;i++) aux[count[digit(a[i],d)]++]=a[i]; for (i=l;i<=r;i++) a[i]=aux[i-1]; } } public static void main(String[]args){ int a[]=new int[]{3,6,5,7,4,8,9}; radixLSD(a,0,a.length-1); for (int i=0;i<a.length;i++){ System.out.println(a[i]); } } public static int digit(int n,int d){ return (n>>d)&1; } } but it show me mistake java.lang.ArrayIndexOutOfBoundsException: -1 at LSD.radixLSD(LSD.java:19) at LSD.main(LSD.java:29) please help me

    Read the article

  • What is it about Fibonacci numbers?

    - by Ian Bishop
    Fibonacci numbers have become a popular introduction to recursion for Computer Science students and there's a strong argument that they persist within nature. For these reasons, many of us are familiar with them. They also exist within Computer Science elsewhere too; in surprisingly efficient data structures and algorithms based upon the sequence. There are two main examples that come to mind: Fibonacci heaps which have better amortized running time than binomial heaps. Fibonacci search which shares O(log N) running time with binary search on an ordered array. Is there some special property of these numbers that gives them an advantage over other numerical sequences? Is it a density quality? What other possible applications could they have? It seems strange to me as there are many natural number sequences that occur in other recursive problems, but I've never seen a Catalan heap.

    Read the article

  • Finding the maximum weight subsequence of an array of positive integers?

    - by BeeBand
    I'm tring to find the maximum weight subsequence of an array of positive integers - the catch is that no adjacent members are allowed in the final subsequence. The exact same question was asked here, and a recursive solution was given by MarkusQ. He provides an explanation, but can anyone help me understand how he has expanded the function? How does this solution take into consideration non-adjacent members?

    Read the article

  • Removing elements from heap

    - by user193138
    I made a heap. I am curious if there's something subtley wrong with my remove function: int Heap::remove() { if (n == 0) exit(1); int temp = arr[0]; arr[0] = arr[--n]; heapDown(0); arr[n] = 0; return temp; } void Heap::heapDown(int i) { int l = left(i); int r = right(i); // comparing parent to left/right child // each has an inner if to handle if the first swap causes a second swap // ie 1 -> 3 -> 5 // 3 5 1 5 1 3 if (l < n && arr[i] < arr[l]) { swap(arr[i], arr[l]); heapDown(l); if (r < n && arr[i] < arr[r]) { swap(arr[i], arr[r]); heapDown(r); } } else if (r < n && arr[i] < arr[r]) { swap(arr[i], arr[r]); heapDown(r); if (l < n && arr[i] < arr[l]) { swap(arr[i], arr[l]); heapDown(l); } } } Here's my output i1i2i3i4i5i6i7 p Active heap: 7 4 6 1 3 2 5 r Removed 7 r Removed 6 p Active heap: 5 3 4 1 2 Here's my teacher's sample output: p Active heap : 7 4 6 1 3 2 5 r Removed 7 r Removed 6 p Active heap : 5 4 2 1 3 s Heapsorted : 1 2 3 4 5 While our outputs are completely different, I do seem to hold maxheap principle of having everything left oriented and for all nodes parent child(in every case I tried). I try to do algs like this from scratch, so maybe I'm just doing something really weird and wrong (I would only consider it "wrong" if it's O(lg n), as removes are intended to be for heaps). Is there anything in particular "wrong" about my remove? Thanks, http://ideone.com/PPh4eQ

    Read the article

  • Fast dot product for a very special case

    - by psihodelia
    Given a vector X of size L, where every scalar element of X is from a binary set {0,1}, it is to find a dot product z=dot(X,Y) if vector Y of size L consists of the integer-valued elements. I suggest, there must exist a very fast way to do it. Let's say we have L=4; X[L]={1, 0, 0, 1}; Y[L]={-4, 2, 1, 0} and we have to find z=X[0]*Y[0] + X[1]*Y[1] + X[2]*Y[2] + X[3]*Y[3] (which in this case will give us -4). It is obvious that X can be represented using binary digits, e.g. an integer type int32 for L=32. Then, all what we have to do is to find a dot product of this integer with an array of 32 integers. Do you have any idea or suggestions how to do it very fast?

    Read the article

  • How to sort a list so that managers are always ahead of their subordinates (How do I do a topologica

    - by James Black
    I am working on a project using Groovy, and I would like to take an array of employees, so that no manager follows their subordinates in the array. The reason being that I need to add people to a database and I would prefer not to do it in two passes. So, I basically have: <employees> <employee> <employeeid>12</employeeid> <manager>3</manager> </employee> <employee> <employeeid>1</employeeid> <manager></manager> </employee> <employee> <employeeid>3</employeeid> <manager>1</manager> </employee> </employees> So, it should be sorted as such: employeeid = 1 employeeid = 3 employeeid = 12 The first person should have a null for managers. I am thinking about a binary tree representation, but I expect it will be very unbalanced, and I am not certain the best way to do this using Groovy properly. Is there a way to do this that isn't going to involve using nested loops?

    Read the article

  • Programming Contest Question: Counting Polyominos

    - by Martijn Courteaux
    Hi, An example question for a programming contest was to write a program that finds out how much polyominos are possible with a given number of stones. So for two stones (n = 2) there is only one polyominos: XX You might think this is a second solution: X X But it isn't. The polyominos are not unique if you can rotate them. So, for 4 stones (n = 4), there are 7 solutions: X X XX X X X X X X XX X XX XX XX X X X XX X X XX The application has to be able to find the solution for 1 <= n <=10 PS: Using the list of polyominos on Wikipedia isn't allowed ;) EDIT: Of course the question is: How to do this in Java, C/C++, C#

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 123 124 125 126 127 128 129 130 131 132 133 134  | Next Page >