Hello, I am having a bizarre Haskell problem that I am having difficulty debugging. I am not positive this is a compiler problem, but my results are not making any sense.
I have attached a few source files which compiled with ghc-5.04.2 running under Win95. The files were compiled as: ghc -c DFT.lhs ghc -c FFT1.lhs ghc -c FFT2.lhs ghc -c Main1.hs ghc -c Mail2.hs ghc -o test1 Main1.o FFT1.o DFT.o ghc -o test2 Main2.o FFT2.o DFT.o Running test1 gives the following results (the last line is wrong): foo 19: [1,2,4,8,16,13,7,14,9,18,17,15,11,3,6,12,5,10] rader1 19: [1,2,4,8,16,13,7,14,9,18,17,15,11,3,6,12,5,10] foo 23: [1,5,2,10,4,20,8,17,16,11,9,22,18,21,13,19,3,15,6,7,12,14] rader1 23: [1,5,2,10,4,20,8,17,16,11,9,22,18,21,1,4,8,18,22,6,19,2] Running test2 gives the following results (these are the results I expect): foo 19: [1,2,4,8,16,13,7,14,9,18,17,15,11,3,6,12,5,10] rader1 19: [1,2,4,8,16,13,7,14,9,18,17,15,11,3,6,12,5,10] foo 23: [1,5,2,10,4,20,8,17,16,11,9,22,18,21,13,19,3,15,6,7,12,14] rader1 23: [1,5,2,10,4,20,8,17,16,11,9,22,18,21,13,19,3,15,6,7,12,14] The only difference bewteen the sources is that in FFT1.lhs, lines 215 and 217 are present, while in FFT2.lhs, they are commented out. Note that these two lines reference the parameter, f. Also note that rader1 calls foo, so I am confused as to how that can produce different results, as test1 shows. FFT1.rader1 works for all n <= 19, but fails for n >= 23 (n has to be prime, however). Also, if I copy the offending code from FFT1.lhs to a separate file, then I get the results I expect, but this is a less than ideal solution. ghc-5.04.2 was installed with the Windows Installer from the website. If you play with the code, foo n should produce a permutation of the sequence [1..(n-1)] for all prime n (ie, foo n produces the permutation for a generator of the Galois field n). I appologize in advance if this is a bug on my part, but based on what I am seeing, I am getting results that should not happen. Thanks. -- Matthew Donadio ([EMAIL PROTECTED])
FFT2.lhs
Description: haskellprogram
Main2.hs
Description: haskellprogram
DFT.lhs
Description: haskellprogram
FFT1.lhs
Description: haskellprogram
Main1.hs
Description: haskellprogram
