GRASS GIS 8 Programmer's Manual
8.2.2dev(2023)-3d2c704037
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GIS Library - Pseudo-random number generation. More...
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <grass/gis.h>
#include <grass/glocale.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
Go to the source code of this file.
Macros | |
#define | LO(x) ((x) & 0xFFFFU) |
#define | HI(x) ((x) >> 16) |
Typedefs | |
typedef unsigned short | uint16 |
typedef unsigned int | uint32 |
typedef signed int | int32 |
Functions | |
void | G_srand48 (long seedval) |
Seed the pseudo-random number generator. More... | |
long | G_srand48_auto (void) |
Seed the pseudo-random number generator from the time and PID. More... | |
long | G_lrand48 (void) |
Generate an integer in the range [0, 2^31) More... | |
long | G_mrand48 (void) |
Generate an integer in the range [-2^31, 2^31) More... | |
double | G_drand48 (void) |
Generate a floating-point value in the range [0,1) More... | |
GIS Library - Pseudo-random number generation.
(C) 2014 by the GRASS Development Team
This program is free software under the GNU General Public License (>=v2). Read the file COPYING that comes with GRASS for details.
Definition in file lrand48.c.
double G_drand48 | ( | void | ) |
Generate a floating-point value in the range [0,1)
Definition at line 158 of file lrand48.c.
References r.
Referenced by G_math_rand().
long G_lrand48 | ( | void | ) |
long G_mrand48 | ( | void | ) |
void G_srand48 | ( | long | seedval | ) |
Seed the pseudo-random number generator.
seedval | 32-bit integer used to seed the PRNG |
Definition at line 53 of file lrand48.c.
References x.
Referenced by G_math_srand(), and G_srand48_auto().
long G_srand48_auto | ( | void | ) |
Seed the pseudo-random number generator from the time and PID.
A weak hash of the current time and PID is generated and used to seed the PRNG
Definition at line 71 of file lrand48.c.
References _, G_fatal_error(), G_srand48(), getenv(), NULL, and t.
Referenced by G_math_srand_auto().