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19025d77ad
Reorganized. Created a new top level include directory that will hold all of Trick's header files. Moved all of the Trick headers to this directory. Created a libexec directory that holds all of the executables that users don't need to execute directly. Changed all of the executables remaining in bin to start with "trick-". In the sim_services directories changed all source files to find the Trick headers in their new location. Since all of the include files are gone in sim_services, removed the src directories as well, moving all of the source files up a level. Moved the makefiles, docs, man, and other architecture independent files into a top level share directory. Renamed lib_${TRICK_HOST_CPU} to lib64 or lib depending on the platform we're currently on.
refs #63
45 lines
1.6 KiB
C
45 lines
1.6 KiB
C
/*
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PURPOSE: (Generate a random number consistent with a Gaussian distribution.)
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ASSUMPTIONS AND LIMITATIONS: ((State spaces for independent processes requiring random numbers are not tracked.)
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(Range is specified in standard deviations; i.e. if a range of 3 sigma is specified, then NO numbers greater than
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the plus/minus 3 sigma value will be returned.) (Automatic Seed))
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PROGRAMMERS: (((Robert W. Bailey) (LinCom Corp) (4/15/91) (Trick-CR-00009) (SAFR Model))) */
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#include <stdlib.h>
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#include "trick/trick_math.h"
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#define MAX_VALUE 32768.0 /* 32768 = 2**15 */
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double drandom_gaussian( /* Return: Random number consistent with Gaussian distribution */
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double std_deviation, /* In: One standard deviation */
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int range)
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{ /* In: Plus/Minus range for Gaussian output in standard deviations */
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int i;
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double out;
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double number = 0.0;
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for (i = 0; i < 2 * range; i++) {
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/* Call rand() 2*range times to get plus/minus range sigma output */
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/* Normalize output of rand to the range of [-0.5,0.5] */
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#ifdef __linux
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out = (((double) rand()) / RAND_MAX) - 0.5;
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#elif __APPLE__
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out = (((double) rand()) / LONG_MAX) - 0.5;
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#else
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out = (((double) rand()) / MAX_VALUE) - 0.5;
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#endif
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/* Scale normalized output by one sigma value and sum to previous normalized values */
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number += (std_deviation * out);
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}
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/* Resulting summed value is a gaussian random number */
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return (number);
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}
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