construct a function which randomly change one bit a column

Ok,im trying to write a function on matlab which can randomly change one bit per column in matrix, for example like , if i have have a 4*4 matrix , i wanna the out put has one bit changed for each column.

for convenience i set up all my data 0 and 1. and basic idea of 'change' is flip 0 to 1 or 1 to 0.

i start with round(rand(4,4)) to get a random matrix, but how can i write the rest of the function?

[Walter Roberson]

How many bits per item? Double precision is 53 bits of precision, 10 bits of exponent, and 1 bit of sign, but with a small bit of work it can be changed to unsigned 64 bit integer -- but earlier MATLAB could not work with 64 bit unsigned integers properly.

Answer 1

[Matt Fig]

A = round(rand(4,4));  % The initial matrix.
% Given A, use this to change one random element per column.
[m,n] = size(A);       % Just to be general...
idx = ceil(rand(1,n)*m)+(0:n-1)*m;
A(idx) = ~A(idx)