#include <stdio.h>
#define A1 7141
#define C1 54773
#define M1 259200
#define RM1 (1.0 / M1)
#define A2 8121
#define C2 28411
#define M2 134456
#define RM2 (1.0 / M2)
#define A3 4561
#define C3 51349
#define M3 243000
#define MASK 131071
float uran3( int *x )
/*---------------------------------------------------------------------
* This routine generates uniformly distributed random numbers in the
* range [0, 1) using the linear congruential method.
* Actually, 3 separate generators are used, generating the upper and
* lower halves of the output and controlling a shuffling routine.
*
* Notes:
* 1. A negative seed value initializes the sequence. The returned
* seed is 1.
* 2. The values A,C, and M are taken from _Numerical Recipes in C_,
* p.211 and are claimed to yield maximal length sequences of period
* M and to pass Knuth's spectral test for dimensions 2, 3, 4, 5 & 6.
*---------------------------------------------------------------------
*/
{ static long ix1, ix2, ix3;
static float r[98];
static int iff = 0;
float temp;
int j;
/* init on first call or when *x is negative */
if ( *x < 0 || iff == 0 ) {
iff = 1;
ix1 = (C1 - *x) % M1;
ix1 = (A1 * ix1 + C1) % M1;
ix2 = ix1 % M2;
ix1 = (A1 * ix1 + C1) % M1;
ix3 = ix1 % M3;
for ( j = 1; j < 97; j++ ) {
ix1 = (A1 * ix1 + C1) % M1;
ix2 = (A2 * ix2 + C2) % M2;
r[j] = (ix1 + ix2 * RM2) * RM1;
}
*x = 1;
}
/* normal operation */
ix1 = (A1 * ix1 + C1) % M1;
ix2 = (A2 * ix2 + C2) % M2;
ix3 = (A3 * ix3 + C3) % M3;
j = 1 + ((97 * ix3) / M3);
temp = r[j];
r[j] = (ix1 + ix2 * RM2) * RM1;
return( temp );
}So I created the following global logic RANDOM (type Numeric)
PARMS(#X) DEFINE #r(98,10.20) #A1 = 7141 #C1 = 54773 #M1 = 259200 #RM1 = (1 / #M1) #A2 = 8121 #C2 = 28411 #M2 = 134456 #RM2 = (1 / #M2) #A3 = 4561 #C3 = 51349 #M3 = 243000 #MASK = 131071 #iff = 0 IF ( #X < 0 OR #iff = 0 ) THEN #iff = 1 #ix1 = REM((#C1 - #X),#M1 ) #ix1 = REM((#A1 * #ix1 + #C1),#M1) #ix2 = REM(#ix1,#M2) #ix1 = REM((#A1 * #ix1 + #C1),#M1) #ix3 = REM(#ix1,#M3) FOR #j = 1 TO 97 #ix1 = REM((#A1 * #ix1 + #C1),#M1) #ix2 = REM((#A2 * #ix2 + #C2),#M2) #r(#j) = (#ix1 + #ix2 * #RM2) * #RM1 ENDFOR #X = 1 ENDIF #ix1 = REM((#A1 * #ix1 + #C1),#M1) #ix2 = REM((#A2 * #ix2 + #C2),#M2) #ix3 = REM((#A3 * #ix3 + #C3),#M3) #j = 1 + ((97 * #ix3) / #M3) #temp = #r(#j) #r(#j) = (#ix1 + #ix2 * #RM2) * #RM1 RETURN(#temp )
But when I call the global, I allways get the same answer back.
My C knowledge is very limited.
Can anyone tell me how the global logic should be created?
