SUBROUTINE banmul(a,n,m1,m2,np,mp,x,b)
      INTEGER m1,m2,mp,n,np
      REAL a(np,mp),b(n),x(n)
      INTEGER i,j,k
      do 12 i=1,n
        b(i)=0.
        k=i-m1-1
        do 11 j=max(1,1-k),min(m1+m2+1,n-k)
          b(i)=b(i)+a(i,j)*x(j+k)
11      continue
12    continue
      return
      END