HP MLIB User's Guide Vol. 1 7th Ed.

Chapter 2 Basic Vector Operations 189
Permute vector F_SPERMUTE/F_DPERMUTE/F_CPERMUTE/F_ZPERMUTE
Input N Number of elements of vector x.
P REAL array, minimum length (N - 1) x |incp| + 1.
INCP Increment for the array p. A vector p having component
p
i
, i = 1,..., n, is stored in an array P() with increment
argument incp. The value of incp can be positive or
negative. A negative value of incp applies the
permutation in the opposite direction. incp = 0 is an
illegal value.
X REAL array, minimum length (N - 1) x |incx| + 1.
INCX Increment for the array x. A vector x having component
x
i
, i = 1,..., n, is stored in an array X() with increment
argument incx. If incx > 0 then x
i
is stored in
X (1 + (i - 1) x incx). If incx < 0 then x
i
is stored in
X (1 + (N - i) x |incx|). incx = 0 is an illegal value.