Division in Matlab is giving values close to zero

Question

I have the following code to load a bitmap from file, which is a 256x256 pixel gray scale image:

a = imread('E:\images\pic1.bmp');
a = double(a(:, :, 1));

figure;
imagesc(abs(a));
colormap(gray);
axis off; 
axis equal;
title('Input image');

rpm1 = exp(i * 2 * pi * rand(256));
theta1 = 2 * pi * rand(256);
Iprime1 = fft2((sqrt(a) .* rpm1));
A = abs(Iprime1);
phi1 = angle(Iprime1);

W = A / 2;
Q = cos(phi1 - theta1);
T = W ./ Q

When I inspect output T in Matlab it is a matrix containing values in the range of 0.0000 to 0.0009. However, when I display W and Q separately and calculate T manually for a single element, it comes out to be a non zero value.

What am I missing?