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/ IRIX Base Documentation 2001 May / SGI IRIX Base Documentation 2001 May.iso / usr / share / catman / p_man / cat3 / complib / sdfft2du.z / sdfft2du
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Text File  |  1998-10-30  |  5.9 KB  |  133 lines
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  4. ssssfffffffftttt2222dddduuuu,,,,ddddfffffffftttt2222dddduuuu((((3333FFFF))))                                        ssssfffffffftttt2222dddduuuu,,,,ddddfffffffftttt2222dddduuuu((((3333FFFF))))
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  8. NNNNAAAAMMMMEEEE
  9.      ddddfffffffftttt2222dddduuuu,,,, ssssfffffffftttt2222dddduuuu ---- 2D Real to Complex Fast Fourier Transform.
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  11. FFFFOOOORRRRTTTTRRRRAAAANNNN SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  12.      ssssuuuubbbbrrrroooouuuuttttiiiinnnneeee DDDDFFFFFFFFTTTT2222DDDDUUUU(((( jjjjoooobbbb,,,, nnnn1111,,,, nnnn2222,,,, sssseeeeqqqquuuueeeennnncccceeee,,,, llllddddaaaa,,,, wwwwoooorrrrkkkkssssppppaaaacccceeee ))))
  13.      iiiinnnntttteeeeggggeeeerrrr             jjjjoooobbbb,,,, nnnn1111,,,, nnnn2222,,,, llllddddaaaa
  14.      ddddoooouuuubbbblllleeee pppprrrreeeecccciiiissssiiiioooonnnn    sssseeeeqqqquuuueeeennnncccceeee((((llllddddaaaa,,,,****)))),,,, wwwwoooorrrrkkkkssssppppaaaacccceeee((((****))))
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  16.      ssssuuuubbbbrrrroooouuuuttttiiiinnnneeee SSSSFFFFFFFFTTTT2222DDDDUUUU(((( jjjjoooobbbb,,,, nnnn1111,,,, nnnn2222,,,, sssseeeeqqqquuuueeeennnncccceeee,,,, llllddddaaaa,,,, wwwwoooorrrrkkkkssssppppaaaacccceeee ))))
  17.      iiiinnnntttteeeeggggeeeerrrr             jjjjoooobbbb,,,, nnnn1111,,,, nnnn2222,,,, llllddddaaaa
  18.      rrrreeeeaaaallll                sssseeeeqqqquuuueeeennnncccceeee((((llllddddaaaa,,,,****)))),,,, wwwwoooorrrrkkkkssssppppaaaacccceeee((((****))))
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  21. CCCC SSSSPPPPEEEECCCCIIIIFFFFIIIICCCCAAAATTTTIIIIOOOONNNN
  22.      iiiinnnntttt        ddddfffffffftttt2222dddduuuu(((( iiiinnnntttt jjjjoooobbbb,,,, iiiinnnntttt nnnn1111,,,, iiiinnnntttt nnnn2222,,,,
  23.                          ddddoooouuuubbbblllleeee ****sssseeeeqqqquuuueeeennnncccceeee,,,, iiiinnnntttt llllddddaaaa,,,,
  24.                          ddddoooouuuubbbblllleeee ****wwwwoooorrrrkkkkssssppppaaaacccceeee))))
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  26.      iiiinnnntttt        ssssfffffffftttt2222dddduuuu(((( iiiinnnntttt jjjjoooobbbb,,,, iiiinnnntttt nnnn1111,,,, iiiinnnntttt nnnn2222,,,,
  27.                          ffffllllooooaaaatttt  ****sssseeeeqqqquuuueeeennnncccceeee,,,, iiiinnnntttt llllddddaaaa,,,,
  28.                          ffffllllooooaaaatttt  ****wwwwoooorrrrkkkkssssppppaaaacccceeee))))
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  33. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  34.      DFFT2DU and SFFT2DU compute the 2 dimensional complex Fourier transform
  35.      of a real periodic sequence.
  36.  
  37.      NOTE: These routines are provided only for compatibility with previous
  38.      releases of complib.
  39.  
  40. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRRSSSS
  41.      JJJJOOOOBBBB ---- IIIINNNNTTTTEEEEGGGGEEEERRRR
  42.      On entry specifies whether to perform a forward or backward Fast Fourier
  43.      Transform:
  44.          JOB = -1,  forward FFT
  45.          JOB =  1,  backward FFT Unchanged on exit.
  46.  
  47.      NNNN1111 ---- IIIINNNNTTTTEEEEGGGGEEEERRRR....
  48.      On entry, N1 specifies the number of elements in the first dimension of
  49.      the sequence.  Unchanged on exit.
  50.  
  51.      NNNN2222 ---- IIIINNNNTTTTEEEEGGGGEEEERRRR....
  52.      On entry, N2 specifies the number of elements in the second dimension of
  53.      the sequence.  Unchanged on exit.
  54.  
  55.      SSSSEEEEQQQQUUUUEEEENNNNCCCCEEEE ---- AAAArrrrrrrraaaayyyy....
  56.      Array of DIMENSION ( LDA, n2 ).  Array containing the (lda*n2) elements
  57.      for the FFT.  On exit, SEQUENCE is overwritten by the 2D transform.
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  63.                                                                         PPPPaaaaggggeeee 1111
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  70. ssssfffffffftttt2222dddduuuu,,,,ddddfffffffftttt2222dddduuuu((((3333FFFF))))                                        ssssfffffffftttt2222dddduuuu,,,,ddddfffffffftttt2222dddduuuu((((3333FFFF))))
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  74.      LLLLDDDDAAAA ---- IIIINNNNTTTTEEEEGGGGEEEERRRR....
  75.      On entry, LDA specifies the first dimension of the array SEQUENCE as
  76.      declared in the calling (sub)program. LDA must be at least max( 1,
  77.      2*((N1+2)/2) ).  Unchanged on exit.
  78.  
  79.      WWWWOOOORRRRKKKKSSSSPPPPAAAACCCCEEEE ---- AAAArrrrrrrraaaayyyy....
  80.      Array of dimension at least (N1+15) + 2*(N2+15).  Array containing the
  81.      Sines/Cosines and factorization of N1 and N2.  WORKSPACE needs to be
  82.      initialized by a call to sfft2dui or dfft2dui.
  83.  
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  85. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  86.      o32fft
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  129.                                                                         PPPPaaaaggggeeee 2222
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