Vector products: Difference between revisions

=={{header|AWK}}==

<lang awk>#!/usr/bin/awk -f

BEGIN {

a[1] = 3; a[2]= 4; a[3] = 5;

b[1] = 4; b[2]= 3; b[3] = 5;

c[1] = -5; c[2]= -12; c[3] = -13;

print "a = ",printVec(a);

print "b = ",printVec(b);

print "c = ",printVec(c);

print "a.b = ",dot(a,b);

## upper case variables are used as temporary or intermediate results

cross(a,b,D);print "a.b = ",printVec(D);

cross(b,c,D);print "a.(b x c) = ",dot(a,D);

cross(b,c,D);cross(a,D,E); print "a x (b x c) = ",printVec(E);

}

function dot(A,B) {

return A[1]*B[1]+A[2]*B[2]+A[3]*B[3];

}

function cross(A,B,C) {

C[1] = A[2]*B[3]-A[3]*B[2];

C[2] = A[3]*B[1]-A[1]*B[3];

C[3] = A[1]*B[2]-A[2]*B[1];

}

function printVec(C) {

return "[ "C[1]" "C[2]" "C[3]" ]";

}</lang>

Output:

<pre>a = [ 3 4 5 ]

b = [ 4 3 5 ]

c = [ -5 -12 -13 ]

A.b = 49

a.b = [ 5 5 -7 ]

a.(b x c) = 6

a x (b x c) = [ -267 204 -3 ]

</pre>