Large archive problem

Will Woods will at brain.ncl.ac.uk
Sat Mar 31 22:14:59 CEST 2001


Hello again,

The problem appears to be with the routines write_unsigned(..) and
read_unsigned(..) in archive.cpp. They work fine for values less than 128,
but as an example, try passing 128. The former writes only one byte (and
maybe there should be a char cast there??), but the read algorithm reads
in two bytes.

Sorry I don't have the fix for this, I just implemented a hack of always
writing out precisely four bytes every time, which works for me at the
moment...


Hope this helps.

Will



On Fri, 30 Mar 2001, Will Woods wrote:

> 
> 
> Hi,
> 
> I am working with large matrices (~100x100) and had trouble with restoring
> archives of them. I wrote the attached test program which just adds the
> same expression to an archive n times (with a unique name each time).
> For any n, the expression can always be retrieved from the original
> archive. But reloading it from file into a new archive object only
> succeeds for n<108 (in this case - other size expressions have different
> limits).
> 
> Great package though. Our problem solution went from several hours under
> Macsyma to just 36 seconds with GiNaC!
> 
> 
> Will
> 
> 
> System:
> 
> GiNaC 0.8.0
> CLN 1.1.0
> Linux Mandrake 7.2
> AMD 700Mhz 128Mb
> 
> 
> 
> 
> 




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