At 12:25 -0500 2007/01/15, John Randall wrote:
Joey K Tuttle wrote:
On my G5 iMac -
x=: 1000 1000 [EMAIL PROTECTED] 0 NB. random real matrix
6!:2 'y=: %. x' NB. invert it
13.7781
>./|, (=i.1000) - x +/ .* y NB. how accurate?
1.97126e_13
Random matrices tend to be numerically stable. Unstable ones crop up all
the time.
hilbert=:]\ %@(i.&.<:@+:)
x=:hilbert 10
y=:%.x
>./|, (=i.10) - x +/ .* y
0.108042
Best wishes,
John
I agree/understand - but the original enquiry seemed
to be implying some kind of size limit... I was just
noting that awhile back I found it amusing/interesting
that I could invert a 1000 x 1000 matrix on my desktop
machine that is not all that much bigger than a laptop -
even with its 20 inch screen... (thinking back to the
days of machines like the IBM 3090 mainframe... :)
- joey
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