Karim BELABAS on Fri, 10 Jan 2003 00:59:49 +0100 (MET)

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Re: qflllgram() infinite loop

On Wed, 8 Jan 2003, Igor Schein wrote:
> qflllgram(matid(229))
> never finishes at 4MB stack.
> Last time it worked was Nov 9 2002.
> If I double the stack, it works fine.

Not an infinite loop, intensive (and almost hopeless) garbage collection.
You're operating in huge dimension and very small space, so that 99.99% of
the running time is spent in desperation GC.

I have reduced memory use for such very sparse matrices, so the above is
fixed. But the same phenomenon is likely to occur again, in larger

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