8 Apr
2004
8 Apr
'04
2:59 p.m.
Russell Hind wrote:
It isn't too terrible, but to invert it it must be square...
Well, the bit I need to invert is prod(trans(X), X) so X is 500 x 5. Is this possible?
X is 500x5 trans(X) is 5x500 prod(trans(X),X) is 5x5, which is a square matrix. So, yes, it can be inverted (all other requirements assumed satisfied...). And if it's 5x5 the lu_ functions are perfect. In fact, you could probably invert it by hand ;-) -- Angus