Files
piscal/dataassim/math/numrec/f77_sources/chint.for
T
2016-02-03 18:52:05 +00:00

19 lines
408 B
Fortran

SUBROUTINE chint(a,b,c,cint,n)
INTEGER n
REAL a,b,c(n),cint(n)
INTEGER j
REAL con,fac,sum
con=0.25*(b-a)
sum=0.
fac=1.
do 11 j=2,n-1
cint(j)=con*(c(j-1)-c(j+1))/(j-1)
sum=sum+fac*cint(j)
fac=-fac
11 continue
cint(n)=con*c(n-1)/(n-1)
sum=sum+fac*cint(n)
cint(1)=2.*sum
return
END