All Questions
100 questions
13votes
5answers
2kviews
solve n*m matrix processing in less time
I want to solve a problem in less time complexity. Here are the details: Given an n*m matrix, n rows and m columns. Initially, the matrix is empty filled with 0s. ...
- 372
3votes
1answer
177views
Snail matrix in Java - version III (generalizing)
Once again, in the previous version, Alexander Ivanchenko helped me with his awesome answer. Now, I have improved the toString() and, also, generalized the class ...
- 30.2k
5votes
1answer
333views
Snail matrix in Java - version II
(This post is the continuation of Snail matrix in Java. Also, this post has an continuation.) As previously, a snail matrix is any square matrix \$M_n = \mathbb{N}^{n \times n}\$ with cell elements ...
- 30.2k
6votes
2answers
903views
Snail matrix in Java
(This post has an continuation: Snail matrix in Java - version II.) Inspired by this post, I decided to solve that problem in Java. The idea is to decide on an \$n \in \mathbb{N}\$, create a square ...
- 30.2k
14votes
4answers
2kviews
Create a snail matrix
Statement: Create a script that, given an integer \$n\$, create a square matrix of dimensions \$n \times n\$ with the numbers from \$1\$ to \$n^2\$, arranged in a snail pattern. Example: ...
- 631
8votes
2answers
482views
Image Rotation and Transpose Functions Implementation in C++
This is a follow-up question for Gaussian Fisheye Image Generator Implementation in C++ and An Updated Multi-dimensional Image Data Structure with Variadic Template Functions in C++. I am trying to ...
- 7,068
6votes
1answer
264views
C++ Eigen/Mex function to perform two pagewise convolutions on a 3D matrix with a simple kernel
I am trying to accelerate an algorithm where I am computing a 2D variance of many complex matrices stored as pages of a 3D array in Matlab. My implementation uses a Mex function with the C++ Matlab ...
- 407
3votes
1answer
350views
How can I optimize double for loop in matrix
I am trying to optimize a function called place_block. It is meant to give the best row, col coordinate in the matrix to place a given block of row and column size. ...
1vote
0answers
80views
S_n covariance calculation function
I am trying to understand the estimator proposed in ["Multidimensional outlier detection and robust estimation using Sn covariance"][1]. I wrote the code in a basic line-by-line form which ...
3votes
1answer
423views
Cosine similarity calculation in Rust, which is slower than NumPy
I'm running this in release mode. Currently, the following function takes around 6.7 seconds to run on my computer vs 3.7 seconds on Python. I know that Numpy is just calling to C, but I'm trying to ...
5votes
1answer
187views
С++: Find max element from section in matrix
I'm a newbie in programming. Could you please check my code and give any refactoring ideas, tips, etc... how it can be improved. I wrote a code to perform the following task: Find in randomly filled ...
3votes
1answer
168views
Dictionary based non-local mean implementation in Matlab
Given a dictionary including multiple X-Y pairs where X, Y are both three dimensional structure. dictionaryBasedNonlocalMean function returns a ...
- 7,068
3votes
1answer
143views
Three-dimensional DCT spatial frequency components illustration
I am attempting to make three-dimensional discrete cosine transformation spatial frequency components illustration. The 3D cubes is used to present the level of each coefficient. The more bright the ...
- 7,068
4votes
1answer
207views
Parallel 3D Discrete Cosine Transformation Implementation in Matlab
I am trying to implement 3D Discrete Cosine Transformation calculation in Matlab with parallel computing parfor. The formula of 3D Discrete Cosine Transformation is ...
- 7,068
5votes
1answer
450views
2D Matrix in C++20 and Strassen's algorithm
I wrote C++20 implementation of a simple matrix class and its usage in Strassen's \$O(n^{lg_2{7}})\$ matrix multiplication algorithm. Live demo: https://wandbox.org/permlink/JaSC8fQccFbcl1QY (For n = ...
- 1,713
