projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 9fcc6ccb KM |
1 | .\" Copyright (c) 1983 Regents of the University of California. |
| 2 | .\" All rights reserved. The Berkeley software License Agreement | |
| 3 | .\" specifies the terms and conditions for redistribution. | |
| 4 | .\" | |
| 63d908a2 | 5 | .\" @(#)rand.3 6.1 (Berkeley) %G% |
| 9fcc6ccb | 6 | .\" |
| 63d908a2 | 7 | .TH RAND 3F "" |
| 9fcc6ccb KM |
8 | .UC 5 |
| 9 | .SH NAME | |
| 10 | rand, drand, irand \- return random values | |
| 11 | .SH SYNOPSIS | |
| 12 | .B function irand (iflag) | |
| 13 | .sp 1 | |
| 14 | .B function rand (iflag) | |
| 15 | .sp 1 | |
| 16 | .B double precision function drand (iflag) | |
| 17 | .SH DESCRIPTION | |
| 63d908a2 KM |
18 | .ft B |
| 19 | The newer random(3f) should be used in new applications; | |
| 20 | rand remains for compatibilty. | |
| 21 | .ft R | |
| 22 | .PP | |
| 9fcc6ccb KM |
23 | These functions use |
| 24 | .IR rand (3C) | |
| 25 | to generate sequences of random numbers. | |
| 26 | If | |
| 27 | .I iflag | |
| 28 | is '1', the generator is restarted and the first random value is returned. | |
| 29 | If | |
| 30 | .I iflag | |
| 31 | is otherwise non-zero, it is used as a new seed for the random number | |
| 32 | generator, and the first new random value is returned. | |
| 33 | .PP | |
| 34 | .I Irand | |
| 35 | returns positive integers in the range 0 through 2147483647. | |
| 36 | .I Rand | |
| 37 | and | |
| 38 | .I drand | |
| 39 | return values in the range 0. through 1.0 . | |
| 40 | .SH FILES | |
| 41 | .ie \nM /usr/ucb/lib/libF77.a | |
| 42 | .el /usr/lib/libF77.a | |
| 43 | .SH "SEE ALSO" | |
| 63d908a2 | 44 | random(3F), rand(3C) |
| 9fcc6ccb KM |
45 | .SH BUGS |
| 46 | The algorithm returns a 15 bit quantity on the PDP11; a 31 bit quantity | |
| 47 | on the VAX. | |
| 48 | .I Irand | |
| 49 | on the PDP11 calls | |
| 50 | .IR rand (3C) | |
| 51 | twice to form a 31 bit quantity, but bit 15 will always be 0. |