I was just trying out FFT routines from Numerical Recipes.
To my great surprise I made the observation that the old
F77 routine 'realft' (for an array of 1024 real data points)
is twice as fast as the newer F90 version of it. I compiled
both with the same NAGWare f95 compiler and run it on a
233 MHz Pentium-I PC. I know that the F90 versions are
written with regard to effective use on parallel processors,
but didn't expect such a dramatic loss of performance on a
single processor machine.
Can anybody comment on this or has made similar experience?
Thanks in advance for any reply,
Roland
PS: This post has also been sent to comp.lang.fortran .
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