\(\newcommand{\W}[1]{ \; #1 \; }\) \(\newcommand{\R}[1]{ {\rm #1} }\) \(\newcommand{\B}[1]{ {\bf #1} }\) \(\newcommand{\D}[2]{ \frac{\partial #1}{\partial #2} }\) \(\newcommand{\DD}[3]{ \frac{\partial^2 #1}{\partial #2 \partial #3} }\) \(\newcommand{\Dpow}[2]{ \frac{\partial^{#1}}{\partial {#2}^{#1}} }\) \(\newcommand{\dpow}[2]{ \frac{ {\rm d}^{#1}}{{\rm d}\, {#2}^{#1}} }\)

pow_int

View page source

The Integer Power Function

Syntax

# include <cppad/utility/pow_int.hpp>

z = pow ( x , y )

See Also

pow

Purpose

Determines the value of the power function

\[{\rm pow} (x, y) = x^y\]

for integer exponents n using multiplication and possibly division to compute the value. The other CppAD pow function may use logarithms and exponentiation to compute derivatives of the same value (which will not work if x is less than or equal zero).

Include

The file cppad/utility/pow_int.hpp is included by cppad/cppad.hpp but it can also be included separately with out the rest of the CppAD routines. Including this file defines this version of the pow within the CppAD namespace.

x

The argument x has prototype

const Type & x

y

The argument y has prototype

const int& y

z

The result z has prototype

Type z

Type

The type Type must support the following operations where a and b are Type objects and i is an int :

Operation	Description	Result Type
Type a ( i )	construction of a Type object from an int	Type
a * b	binary multiplication of Type objects	Type
a / b	binary division of Type objects	Type

Operation Sequence

The Type operation sequence used to calculate z is Independent of x .

Example

The file pow_int.cpp is an example and test of this function.