F117 Vector Product of Two 3-Vectors

Subroutine subprogram CROSS computes the vector (or cross) product

$c=a\; xb$

of two 3-vectors $a,b$ .

Structure:

SUBROUTINE subprogram
User Entry Names: CROSS
COMMON Block Names and Lengths: /SLATE/ 40

Usage:

    CALL CROSS(A,B,C)

A,B

( REAL) One-dimensional arrays of length 3, containing the components $(a$₁,a₂,a₃) ,
$(b$₁,b₂,b₃) , respectively.

C

( REAL) On exit, C contains the components $(c$₁,c₂,c₃) of $a\; xb$ , i.e.

$c$₁=a₂b₃-a₃b₂

$c$₂=a₃b₁-a₁b₃

$c$₃=a₁b₂-a₂b₁ .

F118