BASIC SUBROUTINES

A few trivial subroutines used in this book are below:  

subroutine null(     xx, n)
integer i, n;   real xx( n)
do i= 1, n
        xx(i) = 0.
return; end

 

subroutine scale( factor, n, data)
integer i,                n
real factor, data(n)
do i= 1, n
        data(i) = factor * data(i)
return; end

 

subroutine copy( n, xx, yy)
integer i, n;   real xx(n), yy(n)
do i= 1, n
        yy(i) = xx(i)
return; end