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#include "random.h"
#define IM1 2147483563
#define IM2 2147483399
#define AM (1.0/IM1)
#define IMM1 (IM1-1)
#define IA1 40014
#define IA2 40692
#define IQ1 53668
#define IQ2 52774
#define IR1 12211
#define IR2 3791
#define NTAB 32
#define NDIV (1+IMM1/NTAB)
#define EPS 1.2e-7
#define RNMX (1.0-EPS)
float ran2(long *idum)
{
int j;
long k;
static long idum2=123456789;
static long iy=0;
static long iv[NTAB];
float temp;
if (*idum <= 0) {
if (-(*idum)<1) *idum=1;
else *idum = -(*idum);
idum2=(*idum);
for (j=NTAB+7;j>=0;j--) {
k=(*idum)/IQ1;
*idum=IA1*(*idum-k*IQ1)-k*IR1;
if (*idum < 0) *idum += IM1;
if (j < NTAB) iv[j] = *idum;
}
iy=iv[0];
}
k=(*idum)/IQ1;
*idum=IA1*(*idum-k*IQ1)-k*IR1;
if (*idum < 0) *idum += IM1;
k=idum2/IQ2;
idum2=IA2*(idum2-k*IQ2)-k*IR2;
if (idum2 < 0)idum2 += IM2;
j=iy/NDIV;
iy=iv[j]-idum2;
iv[j] = *idum;
if (iy < 1) iy += IMM1;
if ((temp=AM*iy) > RNMX) return RNMX;
else return temp;
}
#define MBIG 1000000000
#define MSEED 161803398
#define MZ 0
#define FAC (1.0/MBIG)
/*According to Knuth, any large MBIG, and any smaller (but still large)
MSEED can be substituted fro the above values*/
float ran3(long *idum)
/*Returns a uniform deviate between 0.0 and 1.0. Set idum to any negative
value to initialize or reinitialize the sequence.*/
{
static int inext,inextp;
static long ma[56];
static int iff=0;
long mj,mk;
int i,ii,k;
if (*idum < 0 || iff ==0) { /*initialization*/
iff=1;
mj=MSEED-(*idum < 0 ? -*idum : *idum);
mj %= MBIG;
ma[55]=mj;
mk=1;
for (i=1;i<=54;i++) {
ii=(21*i) % 55;
ma[ii]=mk;
mk=mj-mk;
if (mk < MZ) mk +=MBIG;
mj=ma[ii];
}
for (k=1;k<=4;k++)
for (i=1;i<=55;i++) {
ma[i] -= ma[1+(i+30) % 55];
if (ma[i] < MZ) ma[i] += MBIG;
}
inext=0;
inextp=31;
*idum=1;
}
/*Here is where we start, except on initialization*/
if (++inext == 56) inext=1;
if (++inextp == 56) inextp=1;
mj=ma[inext]-ma[inextp];
if (mj < MZ) mj += MBIG;
ma[inext]=mj;
return mj*FAC;
}
float gasdev(long * idum)
{
float ran2(long *idum);
static int iset=0;
static float gset;
float fac,rsq,v1,v2;
if (iset == 0) {
do {
v1=2.0*ran2(idum)-1.0;
v2=2.0*ran2(idum)-1.0;
rsq=v1*v1+v2*v2;
} while (rsq >=1.0 || rsq == 0.0);
fac=sqrt(-2.0*log(rsq)/rsq);
gset=v1*fac;
iset=1;
return v2*fac;
} else {
iset=0;
return gset;
}
}