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Check Determinant of 3 by 3 matrix

Syntax
# include <cppad/speed/det_33.hpp>
ok = det_33(xd)

Purpose
This routine can be used to check a method for computing the determinant of a matrix.

Inclusion
The template function det_33 is defined in the CppAD namespace by including the file cppad/speed/det_33.hpp (relative to the CppAD distribution directory). It is only intended for example and testing purposes, so it is not automatically included by cppad.hpp .

x
The argument x has prototype
     const 
Vector &x
. It contains the elements of the matrix  X in row major order; i.e.,  \[
     X_{i,j} = x [ i * 3 + j ]
\] 


d
The argument d has prototype
     const 
Vector &d
. It is tested to see if d[0] it is equal to  \det ( X ) .

Vector
If y is a Vector object, it must support the syntax
     
y[i]
where i has type size_t with value less than 9. This must return a double value corresponding to the i-th element of the vector y. This is the only requirement of the type Vector. (Note that only the first element of the vector d is used.)

ok
The return value ok has prototype
     bool 
ok
It is true, if the determinant d[0] passes the test and false otherwise.

Source Code
The file det_33.hpp contains the source code for this template function.
Input File: cppad/speed/det_33.hpp