Return to rand_.c CVS log

Up to [CSRG BSD Unix] / 42BSD / usr.lib / libF77

Annotation of 42BSD/usr.lib/libF77/rand_.c, revision 1.1.1.1

1.1       root        1: /*
                      2: char id_rand[] = "@(#)rand_.c  1.1";
                      3:  *
                      4:  * Routines to return random values
                      5:  *
                      6:  * calling sequence:
                      7:  *     double precision d, drand
                      8:  *     i = irand(iflag)
                      9:  *     x = rand(iflag)
                     10:  *     d = drand(iflag)
                     11:  * where:
                     12:  *     If arg is 1, generator is restarted. If arg is 0, next value
                     13:  *     is returned. Any other arg is a new seed for the generator.
                     14:  *     Integer values will range from 0 thru 2147483647.
                     15:  *     Real values will range from 0.0 thru 1.0
                     16:  *     (see rand(3))
                     17:  */
                     18: 
                     19: #if    vax
                     20: #define        RANDMAX         2147483647
                     21: #else  vax
                     22: #if    pdp11
                     23: #define        RANDMAX         32767
                     24: #else  pdp11
                     25:        UNKNOWN MACHINE!
                     26: #endif pdp11
                     27: #endif vax
                     28: 
                     29: long irand_(iarg)
                     30: long *iarg;
                     31: {
                     32:        if (*iarg) srand((int)*iarg);
                     33: #if    pdp11
                     34:        return(( ((long)rand()) << 16) | rand());
                     35: #else  pdp11
                     36:        return( rand() );
                     37: #endif pdp11
                     38: }
                     39: 
                     40: float rand_(iarg)
                     41: long *iarg;
                     42: {
                     43:        if (*iarg) srand((int)*iarg);
                     44:        return( (float)(rand())/(float)RANDMAX );
                     45: }
                     46: 
                     47: double drand_(iarg)
                     48: long *iarg;
                     49: {
                     50:        if (*iarg) srand((int)*iarg);
                     51:        return( (double)(rand())/(double)RANDMAX );
                     52: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.