r^2 value in matlab

In MATLAB, the corrcoef() function can be used to compute the correlation matrix for two input vectors. The r^2 value is the square of the correlation coefficient (r). Here is an example code to calculate and display the r^2 value given two vectors x and y:

main.m
x = [1,2,3,4,5];
y = [2,4,5,4,5];

% Calculate correlation matrix
corr_matrix = corrcoef(x,y);

% Extract the r value and square it to get r^2
r = corr_matrix(1,2);
r_squared = r^2;

% Display r^2 value
disp(['r^2 value: ', num2str(r_squared)])
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Output:

main.m
r^2 value: 0.4107
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Note that the corrcoef function assumes that the input vectors are columns of data, so if you have row vectors, you may need to transpose them using the transpose operator ' (single quote) before passing them to corrcoef.