Vector Math Library Functions                      vzpow(3MVEC)



NAME
     vzpow, vcpow - vector complex power functions

SYNOPSIS
     cc [ flag... ] file... -lmvec [ library... ]

     void vzpow(int *n, double complex * restrict z,
          int *stridez, double complex * restrict w, int *stridew,
          double complex * restrict u, int *strideu,
          double * tmp);


     void vcpow(int *n, float complex * restrict z,
          int *stridez, float complex * restrict w, int *stridew,
          float complex * restrict u, int *strideu,
          float * tmp);


DESCRIPTION
     These functions evaluate the complex  function  z^w  for  an
     entire  vector of values at once. The first parameter speci-
     fies the number of values to compute. Subsequent  parameters
     specify  the  argument  and  result  vectors. Each vector is
     described by a pointer to the first element  and  a  stride,
     which is the increment between successive elements. The last
     argument is a pointer to scratch storage; this storage  must
     be  large  enough  to  hold 3 * *n consecutive values of the
     real type corresponding to the complex type of the  argument
     and result.


     Specifically, vzpow(n, z, sz, w, sw, u, su, tmp)  computes
     u[i  *  *su]  = (z[i * *sz])^(w[i * *sw]) for each i = 0, 1,
     ..., *n - 1. The vcpow() function performs the same compu-
     tation for single precision data.


     These functions are not guaranteed to deliver  results  that
     are identical to the results of the cpow(3M) functions given
     the same arguments.

USAGE
     The element count *n must be greater than zero. The  strides
     for   the  argument  and  result  arrays  can  be  arbitrary
     integers, but the arrays themselves must not be the same  or
     overlap.  A zero stride effectively collapses an entire vec-
     tor into a single element. A negative stride causes a vector
     to be accessed in descending memory order, but note that the
     corresponding pointer must still point to the first  element
     of  the  vector  to be used; if the stride is negative, this
     will be the highest-addressed element in memory.  This  con-
     vention  differs  from  the  Level  1  BLAS,  in which array



SunOS 5.11          Last change: 14 Dec 2007                    1






Vector Math Library Functions                      vzpow(3MVEC)



     parameters always refer to the lowest-addressed  element  in
     memory even when negative increments are used.


     These functions assume  that  the  default  round-to-nearest
     rounding  direction  mode  is in effect. On x86, these func-
     tions also assume that the default round-to-64-bit  rounding
     precision  mode is in effect. The result of calling a vector
     function with a non-default rounding mode in effect is unde-
     fined.


     Unlike  the  c99  cpow(3M)  functions,  the  vector  complex
     exponential  functions  make  no  attempt  to handle special
     cases and exceptions; they simply use textbook  formulas  to
     compute  a  complex  exponential in terms of real elementary
     functions. As a result, these functions can raise  different
     exceptions and/or deliver different results from cpow().

ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          Committed                   
    
     MT-Level                     MT-Safe                     
    


SEE ALSO
     cpow(3M), attributes(5)



















SunOS 5.11          Last change: 14 Dec 2007                    2