ISCE_INSAR/components/isceobj/Util/src/dot_sub.F

41 lines
815 B
Fortran

c****************************************************************
subroutine dot(r_u,r_v,r_d)
c****************************************************************
c**
c** FILE NAME: dot.f
c**
c** DATE WRITTEN: 8/3/90
c**
c** PROGRAMMER:Scott Hensley
c**
c** FUNCTIONAL DESCRIPTION: The subroutine takes two vectors and returns
c** their dot product.
c**
c** ROUTINES CALLED:none
c**
c** NOTES: none
c**
c** UPDATE LOG:
c**
c*****************************************************************
implicit none
c INPUT VARIABLES:
real*8 r_v(3),r_u(3) !3x1 vectors
c OUTPUT VARIABLES:
real*8 r_d
c LOCAL VARIABLES:
c PROCESSING STEPS:
c compute vector dot product
r_d = r_v(1)*r_u(1) + r_v(2)*r_u(2) + r_v(3)*r_u(3)
end