Questions tagged [matlab]
MATLAB is a high-level language and interactive programming environment developed by MathWorks. It is the foundation for a number of other tools, including Simulink and various toolboxes that extend the core capabilities.
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Two dimensional bicubic interpolation implementation in Matlab
I am attempting to implement two dimensional bicubic interpolation algorithm in Matlab. The input is a two dimensional array and the output is the interpolated result.
The test input matrix:
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Use XYZ data to create cross sectional profiles across beach terrain, using OS Grid
This might be a slightly long question, but I've recently been doing a bit of R&D on the data processing workflows within the company that I work at and it would be great to see if there are any ...
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Cross-Entropy Minimization - Extreme Code Performance
I'm working on a multivariate cross-entropy minimization model (for more details about it, see this paper, pp. 32-33). It's purpose is to adjust a prior multivariate distribution (in this case, a ...
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Neuroscientific testing
I have written the code below for the following experiment:
Subjects get simultaneous stimulation of left and right thumb and have to tell which one was stimulated "stronger" (with higher intensity, ...
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Reading cell array of vectors with h5py
I have a data stored in .mat files, each .mat contains a cell array of vectors of length ~70. I'm trying to read these .mat files in to Python with h5py, but reading just 1000 cells takes about 7 ...
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Satellite orbit simulation in Matlab using Runge Kutta 4
I have a satellite orbit simulation in Matlab (Using Runge Kutta 4). It seems ugly and I don't know how to fix it.
fx.m file:
function v = fx(t,x,vx)
v = vx;
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MatLab: Plotting Output Electric Field Spectrum
Goal
This code combines two matrices, diagonalizes that matrix, and finds the right and left eigenvectors, right and left eigenvectors are normalized with respect to each other, then it is multiplied ...
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Optimising multiplication of matrix rows with matrix slice/page
I've recently vectorized most of the code for an optimization problem but this one still eludes me. As the procedure and not the actual values are important here, I have replaced the original matrices ...
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Classifying test data into several classes
The following code is to classify the test data into several classes:
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user3804
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fftshift implementation for OpenCV
I'm trying to implement fftshift from matlab for OpenCV. Can you please review the correctness of my algorithm? Have I missed something? Also, is there a better and faster way to do it?
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Implementation of calculation of gamma for RBF SVM
I have implemented the calculation of gamma value for RBF SVM as described in Liu et al (2012) [https://ieeexplore.ieee.org/abstract/document/6246300]. Here's a snapshot of the example from the paper:
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Matlab Code for Convolutional Neural Networks
I am using Matlab to train a convolutional neural network to do a two class image classification problem. I have an imbalanced data set (~1800 images minority class, ~5000 images majority class). As I ...
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Identifying local peaks among some 2D points
The following MATLAB code takes in multiple peak coordinates and heights and eliminates lesser peaks that are within a certain distance threshold of the highest peak of the vicinity. Is there a better ...
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Making interpolations in a 4D matrix
I have Matlab code that is very inefficient and I need to run it several times.
The code is basically a big parfor loop which I guess there is almost impossible to ...
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Linear interpolation Matlab to C++
I don't have a strong mathematics/Matlab background. I would like to convert this Black level correction function from Matlab to C++. Please comment about on the code style and correctness of my ...
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Kullback-Leibler (KL) distance between inside and outside contour code
I am trying implement the distance measurement between two distributions. The detail is described in here and input image . Let short summarize the idea of the paper:
The input image is divided into ...
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Increasing speed of parity check matrix
The code runs fine and takes 100s to complete it for 5 iteration. I need to reduce it to take less time with the same number of iterations.
h = 324 by 648 matrix
The code is that of FFT Belief ...
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Fitness function
I have a fitness function, where inputs x1 to x14 have values between 1:4. Is there a way to make this more efficient? Any ...
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Bi-Directional A* function in MATLAB
I am currently working on my thesis for 3D path planning involving external elements, and I have completed about 1/5 of the total trials that I am doing. For each 1/5 of the trials I am increasing the ...
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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 return a ...
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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 ...
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Custom Model intended to be used for Curve Fitting. Vectorization vs For Loop and jit numba capabilities
I am new to community and please pardon me if I didn't provide information as intended.
This code is supposed to be creating a custom model which will be used with ...
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Convert Java data to Weka-friendly format without using ARFF
recently I've been working on machine learning with Java and Weka, and while I found the .ARFF format easy to understand (you just need an .ARFF file and Weka will do the rest :P), sometimes the ...
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Implementation of Multiclass Perceptron
The following text is from Hal Daumé III's "A Course in Machine Learning" online text book (Page-41).
I implemented the following:
Is the implementation correct?
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user3804