コード例 #1
0
ファイル: multifiles.c プロジェクト: SixByNine/presto
void rewind_multifile(multifile * mfile)
/* Rewind a multifile. */
{
   fseek_multifile(mfile, 0, SEEK_SET);
}
コード例 #2
0
ファイル: twopass.c プロジェクト: ChrisLaidler/presto
void twopassfft_scratch(multifile * infile, multifile * scratch,
                        long long nn, int isign)
{
   long long n1, n2, bb, fp, ii, jj, kk, kind, df;
   int move_size;
   unsigned char *move;
   rawtype *data, *dp;
   double tmp1, tmp2, wtemp, wpi, wpr, wi, wr, delta;

   if (nn < 2)
      return;

   /* Treat the input data as a n1 (rows) x n2 (cols) */
   /* matrix.  Make sure that n2 >= n1.               */

   n1 = good_factor(nn);
   if (n1 == 0) {
      printf("\nLength of FFT in twopassfft_scratch() must be factorable\n\n");
      exit(1);
   }
   n2 = nn / n1;
   bb = find_blocksize(n1, n2);
   if (bb == 0) {
      printf("\nCan't factor the FFT length in twopassfft_scratch()\n");
      printf("   into useful sizes.\n\n");
      exit(1);
   }

   data = gen_rawvect(bb * n2);
   move_size = (bb + n2) / 2;
   move = (unsigned char *) malloc(move_size);

   /* First do n2 transforms of length n1 by  */
   /* fetching size bb x n1 blocks in memory. */

   for (ii = 0; ii < n2; ii += bb) {

      /* Read a n1 (rows) x bb (cols) block of data */

      dp = data;
      fp = sizeof(rawtype) * ii;
      df = sizeof(rawtype) * n2;
      for (jj = 0; jj < n1; jj++) {
         fseek_multifile(infile, fp, SEEK_SET);
         fread_multifile(dp, sizeof(rawtype), bb, infile);
         dp += bb;              /* Data ptr */
         fp += df;              /* File ptr */
      }

      /* Transpose the n1 (rows) x bb (cols) block of data */

      transpose_fcomplex(data, n1, bb, move, move_size);

      /* Do bb transforms of length n1 */

      for (jj = 0; jj < bb; jj++)
         COMPLEXFFT(data + jj * n1, n1, isign);

      /* Multiply the matrix A(ii,jj) by exp(isign 2 pi i jj ii / nn). */
      /* Use recursion formulas from Numerical Recipes.                */

      for (jj = 0; jj < bb; jj++) {
         delta = isign * TWOPI * (ii + jj) / nn;
         wr = cos(delta);
         wi = sin(delta);
         wtemp = sin(0.5 * delta);
         wpr = -2.0 * wtemp * wtemp;
         wpi = wi;
         kind = jj * n1 + 1;
         for (kk = 1; kk < n1; kk++, kind++) {
            tmp1 = data[kind].r;
            tmp2 = data[kind].i;
            data[kind].r = tmp1 * wr - tmp2 * wi;
            data[kind].i = tmp2 * wr + tmp1 * wi;
            wtemp = wr;
            wr = wtemp * wpr - wi * wpi + wr;
            wi = wi * wpr + wtemp * wpi + wi;
         }
      }
      fwrite_multifile(data, sizeof(rawtype), bb * n1, scratch);
   }

   /* Now do n1 transforms of length n2 by fetching  */
   /* groups of size n2 (rows) x bb (cols) blocks.   */

   for (ii = 0; ii < n1; ii += bb) {

      /* Read two n2 (rows) x bb (cols) blocks from the file */

      dp = data;
      fp = sizeof(rawtype) * ii;
      df = sizeof(rawtype) * n1;
      for (jj = 0; jj < n2; jj++) {
         fseek_multifile(scratch, fp, SEEK_SET);
         fread_multifile(dp, sizeof(rawtype), bb, scratch);
         dp += bb;              /* Data ptr */
         fp += df;              /* File ptr */
      }

      /* Transpose the n2 (rows) x bb (cols) block of data */

      transpose_fcomplex(data, n2, bb, move, move_size);

      /* Do bb transforms of length n2 */

      for (jj = 0; jj < bb; jj++)
         COMPLEXFFT(data + jj * n2, n2, isign);

      /* Transpose the bb (rows) x n2 (cols) block of data */

      transpose_fcomplex(data, bb, n2, move, move_size);

      /* Scale the data if needed */

      if (isign == 1) {
         tmp1 = 1.0 / (double) nn;
         for (jj = 0; jj < n2 * bb; jj++) {
            data[jj].r *= tmp1;
            data[jj].i *= tmp1;
         }
      }


      /* Write n2 (rows) x bb (cols) blocks to the file  */

      dp = data;
      fp = sizeof(rawtype) * ii;
      df = sizeof(rawtype) * n1;
      for (jj = 0; jj < n2; jj++) {
         fseek_multifile(infile, fp, SEEK_SET);
         fwrite_multifile(dp, sizeof(rawtype), bb, infile);
         dp += bb;              /* Data ptr */
         fp += df;              /* File ptr */
      }
   }
   free(move);
   vect_free(data);
}
コード例 #3
0
ファイル: test_multifiles.c プロジェクト: SixByNine/presto
int main(int argc, char *argv[])
{
   int ii, numfiles, filelen, datalen;
   multifile *mfile;
   float *data, *scratch;
   char **filenames;

   srand(3);
   if (argc < 4) {
      printf("usage:  test_multifiles numfiles filelen datalen\n");
      exit(0);
   }
   numfiles = atoi(argv[1]);
   filenames = (char **) malloc(sizeof(char *) * numfiles);
   filelen = atoi(argv[2]);
   for (ii = 0; ii < numfiles; ii++) {
      filenames[ii] = calloc(10, 1);
      sprintf(filenames[ii], "test%d.dat", ii);
   }

   /* Generate the data and scratch spaces */

   datalen = atoi(argv[3]);
   data = gen_fvect(datalen);
   scratch = gen_fvect(datalen);
   for (ii = 0; ii < datalen; ii++)
      data[ii] = (float) 2.0 *(rand() / ((double) RAND_MAX)) - 1.0;

   /* Write the data */

   printf("\nWrite test...\n");
   mfile = fopen_multifile(numfiles, filenames, "w", filelen);
   print_multifile(mfile, 1);
   fwrite_multifile(data, sizeof(float), datalen, mfile);
   print_multifile(mfile, 0);
   fclose_multifile(mfile);

   /* Read the data */

   printf("\nRead test...\n");
   mfile = fopen_multifile(numfiles, filenames, "r", 0);
   print_multifile(mfile, 1);
   fread_multifile(scratch, sizeof(float), datalen, mfile);
   print_multifile(mfile, 0);
   fclose_multifile(mfile);

   /* Compare data and scratch */

   for (ii = 0; ii < datalen; ii++) {
      if (scratch[ii] != data[ii])
         printf("Data point %d doesn't match:  %f, %f\n", ii, data[ii], scratch[ii]);
   }

   /* Seek to a random place in the file and check that data */

   printf("\nSeek test...\n");
   {
      long long byteindex;

      mfile = fopen_multifile(numfiles, filenames, "r", 0);
      print_multifile(mfile, 1);
      byteindex = mfile->filelens[0] + mfile->filelens[1]
          - sizeof(float) * 10;
      print_multifile(mfile, 0);
      fseek_multifile(mfile, byteindex, SEEK_SET);
      print_multifile(mfile, 0);
      fread_multifile(scratch + byteindex / sizeof(float), sizeof(float), 30, mfile);
      print_multifile(mfile, 0);
      fclose_multifile(mfile);
   }

   /* Compare data and scratch */

   for (ii = 0; ii < datalen; ii++) {
      if (scratch[ii] != data[ii])
         printf("Data point %d doesn't match:  %f, %f\n", ii, data[ii], scratch[ii]);
   }
   /* Free stuff up */

   vect_free(data);
   vect_free(scratch);
   for (ii = 0; ii < numfiles; ii++)
      free(filenames[ii]);
   free(filenames);
   exit(0);
}