Optimization is the act of improving a method or design. In programming, optimization usually takes the form of improving the efficiency of an algorithm, or reducing the resources it requires (space in memory, on disk, or amount of network traffic, etc.).
6
votes
1answer
43 views
Optimization of aStar in Java
I'm currently looking to optimize my aStar algorithm as my last run through took roughly a minute to generate one path. I've never had to optimize before as I've never run into performance issues, so ...
0
votes
1answer
45 views
Drawing multiple Images
Im trying to draw a lot of fields image for my world generation, all is perfect 64 fps, but if i began to draw all the time the grass it became laggy, like 59 fps (something that musn't happen! :( ), ...
4
votes
0answers
40 views
Evolution simulation speed too slow to scale up
I'm trying to run this code but it is too slow. I know it is long and I don't expect people to read all of it, but I really need help optimizing the EvolvePop ...
2
votes
0answers
39 views
Typeahead Talent Buddy
Problem is Talent Buddy.
Your task is to
write a function that prints to the standard output (stdout) for each query the user name that matches the query
if there are multiple user names ...
3
votes
1answer
45 views
Platform independant thread pool v4
This is a continuation of this question.
Following the previous advise, the thread pool now can handle almost all types of input, except for one key form, where the function/functor requires one of ...
2
votes
1answer
36 views
Performance of Codility MaxCounter challenge solution
I'm doing some of the Codility challenges using Ruby. The current challenge is "The MaxCounter," which is described as:
Calculate the values of counters after applying all alternating operations: ...
2
votes
0answers
19 views
Python softmatcher using difflib impracticably slow
I have a softmatch function (below) that takes a donor list and a new entry and looks to see if the given donor already exists. The data is not exact, so I have to use a softmatch to determine ...
6
votes
1answer
76 views
Russian doll envelops
Interview question from the interwebz
You have a set of envelopes of different widths and heights. One
envelope can fit into another if and only if both the width and height
of one envelope ...
9
votes
1answer
352 views
Chunk Generation Performance in C#
I'm working on a game in C#, this game generate new chunk (infinite) when you move around. If I have > 1000 chunks in my list then it become laggy even though I only load the necessary chunks on my ...
3
votes
0answers
39 views
Python Multiprocessing: Using mutable ctype arrays seems to work, yet I am not seeing significant speed-up. Why?
As a brief introduction, I am student working on a body of code which forms part of my Masters' research - this is my first question on SO. My background is in physics and mathematics, so I will ...
4
votes
1answer
47 views
Ignore exceptions when changing column formula in Excel table
The new table feature on Excel is excellent and you can specify a column formula as well as exceptions on the column. However, if you want to change the column formula, Excel will rewrite the whole ...
3
votes
6answers
500 views
Code Hunter 2.06: Count occurrences of 'a' in a string
I'm playing Code Hunt on level 2.06 (loops). This level is about counting the number of "a" in a String.
...
4
votes
2answers
52 views
Cleaning up validator class
I updated my class with more functionality, but I kind if feel like it's a mess or that it can at least be improved by a bit readability, efficiency and/or DRY wise.
Anybody who could see if that can ...
7
votes
2answers
348 views
Optimizing this inefficient TicTacToe configuration parser
On a programming contest I came upon this question:
Given a partially played 3 × 3 tic-tac-toe configuration, write a program to determine which player will have a better chance of winning if the ...
4
votes
2answers
78 views
Validator refactored to be OO
Based on my previous post I completely re-factored my code to make it object oriented.
Anything I could improve when it comes to:
Object oriented code;
Efficiency;
Readability.
Any other ...
1
vote
1answer
33 views
Search a file system for files that match a given pattern
My concerns with this code:
Is there a more efficient way to find files by pattern in Python?
Does os.walk() work in Windows?
Is this code pythonic?
Should ...
5
votes
2answers
56 views
Convert string to multiline text
I made this method that takes any string and transforms it into a multiline text l; each line having the max (character) length specified by the rowLength ...
8
votes
1answer
79 views
Finding largest subset of line segments that don't intersect
I completed a challenge of codeeval called BayBridges. It can be found here. I have uploaded my code on GitHub here.
In summary, the challenge is to take a list of line segments, each specified by ...
4
votes
2answers
63 views
Increasing performance of OpenMP based advection equation solver for Xeon Phi
I am solving linear advection equation in order to learn parallel programming. I am running this code on Xeon Phi co processor. Below is a plot of how it scales up with increasing number of threads. I ...
1
vote
2answers
275 views
The efficiency of looping over nested dictionaries in Python
How to make the following code more efficient?
...
7
votes
2answers
102 views
Performance Issues: Finding Nearest Polygon
Finding the nearest polygon out of a list of polygons seems to be quite a challenge on performance, due to lack of optimization. Consider the following image:
I'll give the concept behind this. The ...
0
votes
0answers
16 views
Sorting an input file by a key [closed]
I'm working on some assignments for a course I have coming up in the Fall, and I was wondering what you guys think of my solution (I know it's not the best, but I want to know what I could do better):
...
5
votes
3answers
260 views
How to increase performance/speed of code that uses .Count() on Lists?
The Test
PublicQuestion_ComplexTest
is taking around 1600ms (1.6 seconds) to run, but used to take 92ms. I have a feeling this is because of recent code changes ...
4
votes
2answers
89 views
Typeahead autocomplete functionality challenge
I'm working on a Talent Buddy challenge . In this challenge you have to design the autocomplete functionality of Twitter. You are given a list of queries and possible usernames. You have to return the ...
3
votes
1answer
59 views
Calculating if a point is within a polygon, or outside of it
Here is the function (along with its support functions):
...
5
votes
4answers
153 views
Faster method to find data using search word?
I need to search through a string array to find every occurrence of "Parameters Table", and between each "Parameters Table" and the next, get another string from a specified index (that remains ...
4
votes
3answers
64 views
String self-similarity
It's a string problem I have been making on Hackerrank. It is executing fine on all test cases except the last two. These last two test case are declaring it "Terminated due to time out".
C programs ...
5
votes
3answers
73 views
Calculating the ranks of classmates' exam grades
The questions from hackerearth:
Geeko is in worry now because an exam is coming up and he has to know
what rank he can get on exams. So he goes back into the the school records
and finds the ...
14
votes
6answers
2k views
Sherlock and The Beast
This is my solution to this question from Hackerrank.
Given N (<= 100000), find the largest N-digit number such that:
The number has only 3 and 5 as its digits.
Number of times 3 ...
4
votes
1answer
49 views
Optimize iteration output to text file
I've written a piece of code which combines given letters in groups of n letters, and writes all the combinations in a text file. This is my first attempt and I wonder if there is an optimal way to do ...
1
vote
0answers
19 views
Optimizing jQuery table building by replacing appends with string concat
I've wrote some code to create a grid of data, however depending on the size of the grid being drawn, IE8 shows a warning message about a long running script.
I've read that multiple appends are a ...
5
votes
1answer
62 views
Calculating “element-wise” the angles between two lists of vectors
Let's say you have two lists of vectors:
v1s = [a, b, c]
v2s = [d, e, f]
I am interested in generating the following ...
3
votes
1answer
75 views
Is there a better way to write these two nested loops in Erlang?
Since one month, I'm learning Erlang and I like it so much.
Today, I wrote an algorithm to solve a problem.
Some time ago, I used two nested for loops in C# to ...
1
vote
0answers
24 views
Avoiding boundaries if-cases when filtering image matrix
I have the following MATLAB Code which I want to optimize.
It's related to an image matrix (2D) which I want to filter.
Though it is MATLAB code, the same problem would arise in C code.
The problem ...
5
votes
1answer
54 views
How can I optimize this SQL ranking generator query?
I have a World Cup fixture app where people can guess the results of the matches. Everything is working great, but each time I update the ranking, it takes 20 minutes for just 3000 users. So there ...
3
votes
1answer
56 views
Quick Hull Algorithm implementation for higher dimensions
I tried to implement the Quick Hull Algorithm for computing the convex hull of a finite set of D-dimensional points. Here is the repository. Algorithm itself:
...
0
votes
0answers
18 views
Memory read/write access efficiency [migrated]
I've heard conflicting information from different sources, and I'm not really sure which one to believe. As such, I'll post what I understand and ask for corrections. Let's say I want to use a 2D ...
9
votes
2answers
72 views
Scalability of running commands from user input
Here is some code I have that has been extracted and shrunk down from a project of mine.
...
6
votes
2answers
373 views
Is there a way to optimise my Perlin noise?
I just started using Perlin noise a few days ago, and the results look quite good. But it takes over 3 seconds to calculate and draw a 1024x1024 bitmap of said noise. I use an array of 1024x1024 to ...
3
votes
2answers
67 views
Optimizing graph analysis
I've implemented the Floyd Warshall algorithm in this problem. However, as this is my first time in handling with adjacency list, I was not able to make it memory efficient.
I used a 1000*1000 and ...
5
votes
0answers
149 views
Puzzle game with sequence numbers
I am currently developing a puzzle game that has sequence numbers. The player has to fill the grid with sequence numbers in ascending order. Starting from 1 the player can move horizontally or across ...
10
votes
1answer
91 views
Sieve of Atkins algorithm
I got the inspiration to write this algorithm from this question. The OP cited the Sieve of Atkin as one of the fastest ways to generate primes. So I figured I would give it a try:
...
6
votes
2answers
228 views
Pinging a URL with libcurl
I've asked a question about pinging a URL before, but I wanted something that was a bit shorter and still just as efficient. libcurl seemed to be the perfect answer. Here is my method:
...
2
votes
2answers
100 views
2
votes
2answers
46 views
Importing tab delimited file into array
I am needing to import a tab delimited text file that has 11 columns and an unknown number of rows (always minimum 3 rows).
I would like to import this text file as an array and be able to call data ...
6
votes
2answers
119 views
Prime Number Speed
I know prime number programs have been beaten to death. I am have been programming for eight years (not that long, but I'm not in my 20s yet and I got a programming job straight out of high school so ...
3
votes
1answer
58 views
Displaying TimeSpan as largest interval (with units) - Part II
[This is a follow-up question to: Displaying TimeSpan as largest interval (with units). The code listed here has been refactored since the original question was posed. Please note that the scope of ...
5
votes
2answers
158 views
Efficient way to get every unique combination of “Pick 1 number from each Group of Numbers”
My question is: Using C# and/or Linq, how can this existing code be improved to be more efficient? (My "Complex" example takes about 5 seconds to run, how to make it faster?)
What the code is ...
5
votes
3answers
283 views
Displaying TimeSpan as largest interval (with units)
The following method is used in a call center application to display an approximation of remaining time. The call center telephone operator would inform the caller that they could perform their ...
3
votes
2answers
81 views
Simplify an if else construct with assignment before if and else
I want to simplify an if: .. else: .. construct:
...
