mpf_get_str() is slow for big numbers?
rob at haptek.com
Sun Nov 30 10:09:52 CET 2003
>rob shaw <rob at haptek.com> writes:
>> The installation of GMP went smoothly on a mac G4 under OS X, but I've
>> noticed that
>> the output of very large numbers via mpf_out_str() is painfully
>Alas, it still uses a quadratic algorithm. The next release will have
>that fixed. One workaround is to scale and convert to an integer,
>since integer output is subquadratic.
...i wrote a routine mpf_out_str16() which is specialized to write
out hex characters to disk directly from the mpf_t variable, without
allocating memory for the string, etc. to write out 25 million hex digits
mpf_out_str() took over 15 hours, the direct version, 3 seconds.
the code, such that it is, is available on request.
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