Mapping pixels of two matrices

Question

Say that I have two matrices of the following sizes:

matrix_1 = 30090x2

matrix_2 = 170x177

Assume here that the number of rows n matrix_1 represents the number of pixels. You can see that the size of matrix_2 is equal to the number of pixels.

What I'm trying to do is map the pixels in matrix_1 to the pixels in matrix_2, such that for example:

matrix_1(1) = matrix_2(1)
matrix_1(2) = matrix_2(2)
matrix_1(3) = matrix_2(3)
......
......
matrix_1(n) = matrix_2(n)

How can I do that in matlab?

Answer 1

Here is an option

  matrix_1 = matrix_2(:);

which copies the elements (all of them) of matrix_2 in one long column.

In your data you said that matrix_1 has two columns, you can add a further empty column by doing, for instance

  matrix_1  = [matrix_1 zeros(size(matrix_1))];

Answer 2

A fast way is first convert both matrix to column vector using the following command: matrix_1=matrix_1(:); matrix_2=matrix_2(:);

And since both matrix now have the same size, you can perform wanted operations.

If you need to restore the matrix to original scale, you can do it by using reshape command matrix_1=reshape(matrix_1, 30090,2)

see following reference: http://www.mathworks.com/help/matlab/ref/reshape.html