Matrix is singular or badly scaled. Please help

I've been working on the attached code for quite some time now and I think I'm close. I keep getting the following warning:

In hopefullyBetterProject (line 55) Warning: Matrix is singular, close to singular or badly scaled. Results may be inaccurate. RCOND = NaN. 
In hopefullyBetterProject (line 74) Warning: Matrix is singular, close to singular or badly scaled. Results may be inaccurate. RCOND = NaN.

Both lines are the same matrix operation:

someVariable = step*(Mmat\Qmat);

I'm not sure what's going wrong here and I think I'm starting to lose what's left of my marbles. Any help with solving or approaching this error would be amazing. Thanks!

Answer 1

[Walter Roberson]

Your values are getting larger and larger in magnitude as you go. When you reach ii = 6, the second Qmat has involves adding numbers large enough that infinity is returned. The result of the \ operator that follows that will involve NaN. In the next iteration of the for loop, when ii = 7, those NaN propagate and give you an all-NaN matrix; at that point you get the warning because the NaN vector cannot be inverted.