Top "Matrix" questions

In mathematics, a matrix (plural matrices) is a rectangular array of numbers, symbols, or expressions, arranged in rows and columns.

How can I create a correlation matrix in R?

I have 92 set of data of same type. I want to make a correlation matrix for any two combination possible. …

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How can I plot a confusion matrix?

I am using scikit-learn for classification of text documents(22000) to 100 classes. I use scikit-learn's confusion matrix method for computing the …

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How can I count the number of elements of a given value in a matrix?

Does anyone know how to count the number of times a value appears in a matrix? For example, if I …

matlab count matrix
Transpose/Unzip Function (inverse of zip)?

I have a list of 2-item tuples and I'd like to convert them to 2 lists where the first contains the …

python list matrix transpose
data type not understood

I'm trying to use a matrix to compute stuff. The code is this import numpy as np # some code mmatrix = …

python matrix numpy
What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and benefit tradeoffs?

It seems that many projects slowly come upon a need to do matrix math, and fall into the trap of …

c++ math matrix linear-algebra
Right way to convert data.frame to a numeric matrix, when df also contains strings?

I have a data frame taken from a .csv-file which contains numeric and character values. I want to convert this …

r if-statement matrix numeric
What are the differences between numpy arrays and matrices? Which one should I use?

What are the advantages and disadvantages of each? From what I've seen, either one can work as a replacement for …

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Finding row index containing maximum value using R

Given the following matrix lets assume I want to find the maximum value in column two: mat <- matrix(…

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Matrix multiplication using arrays

I'm trying to make a simple matrix multiplication method using multidimensional arrays ([2][2]). I'm kinda new at this, and I just …

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