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43 lines
1.4 KiB
Fortran
43 lines
1.4 KiB
Fortran
*DECK RGAUSS
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FUNCTION RGAUSS (XMEAN, SD)
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C***BEGIN PROLOGUE RGAUSS
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C***PURPOSE Generate a normally distributed (Gaussian) random number.
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C***LIBRARY SLATEC (FNLIB)
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C***CATEGORY L6A14
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C***TYPE SINGLE PRECISION (RGAUSS-S)
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C***KEYWORDS FNLIB, GAUSSIAN, NORMAL, RANDOM NUMBER, SPECIAL FUNCTIONS
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C***AUTHOR Fullerton, W., (LANL)
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C***DESCRIPTION
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C
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C Generate a normally distributed random number, i.e., generate random
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C numbers with a Gaussian distribution. These random numbers are not
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C exceptionally good -- especially in the tails of the distribution,
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C but this implementation is simple and suitable for most applications.
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C See R. W. Hamming, Numerical Methods for Scientists and Engineers,
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C McGraw-Hill, 1962, pages 34 and 389.
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C
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C Input Arguments --
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C XMEAN the mean of the Guassian distribution.
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C SD the standard deviation of the Guassian function
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C EXP (-1/2 * (X-XMEAN)**2 / SD**2)
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C
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C***REFERENCES (NONE)
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C***ROUTINES CALLED RAND
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C***REVISION HISTORY (YYMMDD)
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C 770401 DATE WRITTEN
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C 861211 REVISION DATE from Version 3.2
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C 891214 Prologue converted to Version 4.0 format. (BAB)
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C 910819 Added EXTERNAL statement for RAND due to problem on IBM
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C RS 6000. (WRB)
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C***END PROLOGUE RGAUSS
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EXTERNAL RAND
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C***FIRST EXECUTABLE STATEMENT RGAUSS
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RGAUSS = -6.0
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DO 10 I=1,12
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RGAUSS = RGAUSS + RAND(0.0)
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10 CONTINUE
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C
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RGAUSS = XMEAN + SD*RGAUSS
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C
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RETURN
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END
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