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subroutine mult1(A,la,na,B,lb,nb,C,nc)
c This subroutine multiplies together two polynomials a(x) and b(x):
c (for multiplying two polynomials in B)
c Note that la and lb, the dimensions of A and B from the main program
c may be greater than na and na, the dimensions used in the subroutine
c
c a(x) = a0 + a1*x^(1) + a2*x^(2) + ... + a(na)*x^(na)
c
c b(x) = b0 + b1*x^(1) + b2*x^(2) + ... + b(nb)*x^(nb)
c
c
c Note that the general form used here has positive signs for the
c coefficients. The coefficients are stored in elements 0 to na of
c array A and -nb to nc of array B in the order of increasing powers of x, i.e.
c
c A(0:na) = [a0, a1, ... , a(na)]'.
c
c B(0:nb) = [b0, b1, ... , b(nb)]'.
c
c The product c(x) = a(x)b(x), its coefficients are
c stored in the array C = [c0, ... , c(nc)]'.
c Note, nc is the dimensions of the vector c, but all of the vector may not be used
double precision A(0:la),B(0:lb),C(0:nc)
do 1 j = 0,nc
C(j) = 0.0D0
1 continue
do 3 j = 0,na
do 4 k = 0,nb
C(k+j) = C(k+j) + A(j)*B(k)
4 continue
3 continue
c do 2 i = -(na+nb),nnb
c do 3 j = 0,na
c do 4 k = -nb,nnb
c if (k-j .eq. i) then
c C(i) = C(i) + A(j)*B(k)
c end if
c4 continue
c3 continue
c2 continue
return
end
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