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@(@\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}} }@)@
Determinant Using Expansion by Minors

Syntax
# include <cppad/speed/det_by_minor.hpp>
det_by_minor<Scalardet(n)
d = det(a)

Inclusion
The template class det_by_minor is defined in the CppAD namespace by including the file cppad/speed/det_by_minor.hpp (relative to the CppAD distribution directory).

Constructor
The syntax
     det_by_minor<
Scalardet(n)
constructs the object det which can be used for evaluating the determinant of n by n matrices using expansion by minors.

Scalar
The type Scalar must satisfy the same conditions as in the function det_of_minor .

n
The argument n has prototype
     size_t 
n

det
The syntax
     
d = det(a)
returns the determinant of the matrix A using expansion by minors.

a
The argument a has prototype
     const 
Vector &a
It must be a Vector with length @(@ n * n @)@ and with elements of type Scalar . The elements of the @(@ n \times n @)@ matrix @(@ A @)@ are defined, for @(@ i = 0 , \ldots , n-1 @)@ and @(@ j = 0 , \ldots , n-1 @)@, by @[@ A_{i,j} = a[ i * m + j] @]@

d
The return value d has prototype
     
Scalar d
It is equal to the determinant of @(@ A @)@.

Vector
If y is a Vector object, it must support the syntax
     
y[i]
where i has type size_t with value less than @(@ n * n @)@. This must return a Scalar value corresponding to the i-th element of the vector y . This is the only requirement of the type Vector .

Example
The file det_by_minor.cpp contains an example and test of det_by_minor.hpp. It returns true if it succeeds and false otherwise.

Source Code
The file det_by_minor.hpp contains the source for this template function.
Input File: cppad/speed/det_by_minor.hpp