Reshaping with Different Sizes

There are two lines of code in someone's script that I can't figure out how it works. Here is the code and attached is a .mat file with the variables themselves. Note that the .mat file begins with the original regionMat_m, and once you run the code regionMat_m changes.

bar = tmp(rnum(1:rc));
regionMat_m = reshape(bar(regionMat_m),R,C);

bar and regionMat_m have conflicting sizes of 1x156 and 256x400 respectively, so I'm not sure how bar(regionMat_m) even compiles. Once it does compile, I don't see the correlation between the output and the input. Help would be much appreciated!

Sidenote: I know bar is also a MATLAB function for graphing. I don't know why the variable is named bar. I didn't write this code! Just trying to figure out what is going on.

Answer 1

[Matt J]

There is no requirement that an index array be the same size as the array being indexed. Example:

values=[20,30,40]

values = 1×3

20 30 40

values(ones(5))

ans = 5×5

20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20