WSJT-X/gasdev.f

25 lines
552 B
FortranFixed
Raw Normal View History

FUNCTION gasdev(idum)
INTEGER idum
REAL gasdev
CU USES ran1
INTEGER iset
REAL fac,gset,rsq,v1,v2,ran1
SAVE iset,gset
DATA iset/0/
if (iset.eq.0) then
1 v1=2.*ran1(idum)-1.
v2=2.*ran1(idum)-1.
rsq=v1**2+v2**2
if(rsq.ge.1..or.rsq.eq.0.)goto 1
fac=sqrt(-2.*log(rsq)/rsq)
gset=v1*fac
gasdev=v2*fac
iset=1
else
gasdev=gset
iset=0
endif
return
END
C (C) Copr. 1986-92 Numerical Recipes Software *(t9,12.