Returns Indices that Sort a Vector

@(@\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}} }@)@ This is cppad-20221105 documentation. Here is a link to its current documentation . Returns Indices that Sort a Vector
Syntax

# include <cppad/utility/index_sort.hpp>

index_sort(keys, ind)

keys
The argument keys has prototype



    const KeyVector& keys

where KeyVector is a SimpleVector class with elements that support the < operation.

ind
The argument ind has prototype



    SizeVector& ind

where SizeVector is a SimpleVector class with elements of type size_t. The routine CheckSimpleVector will generate an error message if this is not the case.

Input
The size of ind must be the same as the size of keys and the value of its input elements does not matter.

Return
Upon return, ind is a permutation of the set of indices that yields increasing order for keys . In other words, for all i != j ,



    ind[i] != ind[j]

and for i = 0 , ... , size-2 ,



    ( keys[ ind[i+1] ] < keys[ ind[i] ] ) == false

Example
The file index_sort.cpp contains an example and test of this routine. It return true if it succeeds and false otherwise.

Input File: include/cppad/utility/index_sort.hpp