How to calculate single average of all rows and single average of all columns of image?
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I am having a gray image of size 256 by 256 and want to calculate row and column mean. I am able to calculate column mean of image as follow im=imread('E:\xyz.jpg') cmean=mean(mean(im)); In order to take row mean I took transpose of im matrix and then calculated the mean. im1 = transpose(im); rmean=mean(mean(im1));
Column and row mean should be different. But gives the same answer for row and column mean. What is wrong?
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Jan
2017-1-19
As explained in the documentation of doc mean, the dimension to operate on can be defined by the second input:
x = rand(10, 10);
m_dim1 = mean(x, 1);
m_dim2 = mean(x, 2);
If mean(X) and mean(X.') reply the same values, either X is a vector or the means are equal. mean(X) without specifying the dimension operates on the first non-singelton dimension. This is risky: You save half a second during typing, but might spend hours with debugging. So prefer to define the dimension explicitly, because sometime Matlab's smart decisions to guess what you want, are too smart.
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