Hi!
I read at a few places (in the doc and in this blog post : http://blogs.mathworks.com/loren/2007/05/16/purpose-of-inv/ ) that the use of inv in Matlab is not recommended because it is slow and inaccurate.
I am trying to find the reason of this inaccuracy. As of now, Google did not give m interesting result, so I thought someone here could guide me.
Thanks !
I think the point of Loren's blog is not that MATLAB's inv function is particularly slower or more inaccurate than any other numerical implementation of computing a matrix inverse; rather, that in most cases the inverse itself is not needed, and you can proceed by other means (such as solving a linear system using \ - the backslash operator - rather than computing an inverse).
The inaccuracy I mentioned is with the method INV, not MATLAB's implementation of it. You should be using QR, LU, or other methods to solve systems of equations since these methods don't typically require squaring the condition number of the system in question. Using inv typically requires an operation that loses accuracy by squaring the condition number of the original system.
--Loren