From: Brad King <brad.king@ki...> - 2006-07-28 15:46:30
While updating ITK to use the latest vnl version with all the thread
safety changes an FFT test started failing. It turns out that the valid
image was wrong because the old FFT code in prior versions of netlib in
vxl was wrong!
In gpfa2f.c there was code that basically did this:
i__2 = something;
for(...; ll += i__2)
i__2 = something_else;
for(...; jjj += i__2)
An outer-loop control variable was modified inside the loop for use by
the inner loop. This bug was probably introduced by the manual editing
of the C code that occurred while it sat in targetjr or vxl.
The new v3p_netlib library version of gpfa2f.c and other fft routines
have been converted directly from the original fortran source. This has
repaired the fft bug.