1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
#ifndef mcran4_h
#define mcran4_h
#include <nrnconf.h>
#if defined(HAVE_STDINT_H)
#include <stdint.h>
#endif
#if defined(__cplusplus)
extern "C" {
#endif
extern void mcell_ran4_init(uint32_t);
extern double mcell_ran4(uint32_t* high, double* x, unsigned int n, double range);
extern double mcell_ran4a(uint32_t* idx1);
extern uint32_t mcell_iran4(uint32_t* idx1);
extern double nrnRan4dbl(uint32_t* idx1, uint32_t idx2);
extern uint32_t nrnRan4int(uint32_t* idx1, uint32_t idx2);
#if defined(__cplusplus)
}
#endif
#endif
/*
The original ran4 generator was copyrighted by "Numerical Recipes in C"
and therefore has been removed from the NEURON sources and replaced by code
fragments obtained from http://www.inference.phy.cam.ac.uk/bayesys/
by John Skilling
The function mcell_ran4a only returns
a single uniform random number in the distribution 0.0 to 1.0 .
The prototype for mcell_ran4 is the original.
*/
/*
Michael Hines added the prefix mcell to the global names.
These functions were obtained from Tom Bartol <bartol@salk.edu>
who uses them in his mcell program.
He comments:
For MCell, Ran4 has the distinct advantage of generating
streams of random bits not just random numbers. This means that you can
break the 32 bits of a single returned random number into several smaller
chunks without fear of correlations between the chunks. Ran4 is not the
fastest generator in the universe but it's pretty fast (16 million
floating point random numbers per second on my 1GHz Intel PIII and 20
million integer random numbers per second) and of near cryptographic
quality. I've modified it so that a given seed will generate the same
sequence on Intel, Alpha, RS6000, PowerPC, and MIPS architectures (and
probably anything else out there). It's also been modified to generate
arbitrary length vectors of random numbers. This makes generating numbers
more efficient because you can generate many numbers per function call.
MCell generates them in chunks of 10000 at a time.
*/
|
