Check Determinant of 3 by 3 matrix
Keywords: check determinant 3 matrix det_33 correct syntax purpose inclusion x d vector ok source code

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Check Determinant of 3 by 3 matrix
Syntax
`# include <cppad/speed/det_33.hpp>
` `ok = det_33(x, d)`
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