tools/four2eight.c

   1 /* Jan. 2005.
   2
   3    A utility that converts unformatted binary real data files
   4    to unformatted binary double precision data files.
   5
   6    Compile as
   7
   8         cc -o four2eight four2eight.c
   9
  10    If you are running this on a little-endian platform
  11    compile with -DSWAP like so:
  12
  13         cc -o four2eight -DSWAP four2eight.c
  14
  15    Use as
  16
  17         four2eight < RRTM_DATA > RRTM_DATA_DBL  (for example)
  18
  19    JM
  20
  21 */
  22
  23
  24 #include <stdio.h>
  25
  26 int
  27 main()
  28 {
  29    int in, cr, cr1, n ;
  30    int i ;
  31    float x, x1 ;
  32    double y, y1 ;
  33
  34    while (
  35      fread( &in, 1, 4, stdin ) > 0 ) {
  36      swap4(&in, &cr) ;
  37      n = cr ;
  38      cr1 = 2*cr ;
  39      fprintf(stderr, "%d > %d\n",cr,cr1) ;
  40      swap4(&cr1,&cr) ;
  41      fwrite( &cr, 1, 4, stdout ) ;
  42      for ( i = 0 ; i < n ; i += 4 )
  43      {
  44        fread ( &x, 1, 4, stdin ) ;
  45        swap4(&x,&x1) ;
  46        y1 = x1 ;
  47        swap8(&y1,&y) ;
  48        fwrite ( &y, 1, 8, stdout ) ;
  49      }
  50      fread( &in, 1, 4, stdin ) ;
  51      fwrite( &cr, 1, 4, stdout ) ;
  52    }
  53    fprintf(stderr,"\n") ;
  54 }
  55
  56 void
  57 swap4( a, b )
  58    char a[], b[] ;
  59 {
  60 #ifdef SWAP
  61    b[0] = a[3] ;
  62    b[1] = a[2] ;
  63    b[2] = a[1] ;
  64    b[3] = a[0] ;
  65 #else
  66    b[0] = a[0] ;
  67    b[1] = a[1] ;
  68    b[2] = a[2] ;
  69    b[3] = a[3] ;
  70 #endif
  71 }
  72
  73 void
  74 swap8( a, b )
  75    char a[], b[] ;
  76 {
  77 #ifdef SWAP
  78    b[0] = a[7] ;
  79    b[1] = a[6] ;
  80    b[2] = a[5] ;
  81    b[3] = a[4] ;
  82    b[4] = a[3] ;
  83    b[5] = a[2] ;
  84    b[6] = a[1] ;
  85    b[7] = a[0] ;
  86 #else
  87    b[0] = a[0] ;
  88    b[1] = a[1] ;
  89    b[2] = a[2] ;
  90    b[3] = a[3] ;
  91    b[4] = a[4] ;
  92    b[5] = a[5] ;
  93    b[6] = a[6] ;
  94    b[7] = a[7] ;
  95 #endif
  96 }
  97