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Lapack Numerical Precision

PostPosted: Mon Mar 12, 2012 5:07 pm
by ctcsback
When compiling lapack 3.4.0, I get a testing summary, with the following output:


--> LAPACK TESTING SUMMARY <--
Processing LAPACK Testing output found in the TESTING direcory
SUMMARY nb test run numerical error other error
================ =========== ================= ================
REAL 1075083 37 (0.003%) 0 (0.000%)
DOUBLE PRECISION 1061639 201 (0.019%) 0 (0.000%)
COMPLEX 503926 3 (0.001%) 0 (0.000%)
COMPLEX16 528522 27 (0.005%) 0 (0.000%)

--> ALL PRECISIONS 3169170 268 (0.008%) 0 (0.000%)

I'm only using the double routines, and the programs I'm running for my numerical methods seem to be very sensitive to numerical accuracy. The routines I call are DGEMM and DGESV, but how much error is actually attributed to LAPACK? Is it .00019, or does that number mean something else?

Re: Lapack Numerical Precision

PostPosted: Mon Mar 19, 2012 5:49 pm
by admin
Those numbers just count the testing errors in the LAPACK testing suite.
Your numbers are fine. Your programs should be fine.
LAPACK testing suite includes some torture tests that usually fails.
Julie