两个随机数程序.txt

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均匀分布+正态分布

#include <math.h>
const long int MBIG=0x0fffffff;
const long int MSEED=0x03c04ffd;
const int MZ=0;
const double FAC=1.0/MBIG;
//[0,1]均匀分布
double Crand(long *seed)
{
static int inext,inextp,iff=0;
static long ma[56],mj,mk;
int i,j,k;
if(*seed<0 || iff==0)
{
iff=1;
mj=MSEED-(*seed<0? -*seed:*seed);
mj%=MBIG;
ma[55]=mj;
for(mk=1,i=1;i<=54;i++)
{
j=(21*i)%55;
ma[j]=mk;
mk=mj-mk;
if(mk<MZ) mk+=MBIG;
mj=ma[j];
}
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;
*seed=1;
}
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;
}
//G(0,1)高斯分布
double Gauss(long *seed)
{
static int iflag=0;
static double gset;
double fac,Rs,v1,v2;
if(iflag==0)
{
do
{
v1=2.0*Crand(seed)-1.0;
v2=2.0*Crand(seed)-1.0;
Rs=v1*v1+v2*v2;
}while(Rs==0.0 || Rs>=1.0);
fac=(double) sqrt(-2.0*log((double)Rs)/Rs);
gset=v1*fac;
iflag=1;
return v2*fac;
}
else
{
iflag=0;
return gset;
}
}