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// SPDX-License-Identifier: EPL-2.0 OR GPL-2.0-or-later
// SPDX-FileCopyrightText: Bradley M. Bell <bradbell@seanet.com>
// SPDX-FileContributor: 2003-22 Bradley M. Bell
// ----------------------------------------------------------------------------
/*
{xrst_begin base2vec_ad.cpp}
Using base2ad and VecAD together: Example and Test
##################################################
Purpose
*******
This example demonstrate that :ref:`base2ad-name` does not convert
:ref:`VecAD-name` operations as might be expected.
To be specific, this indexing into a VecAD object gets fixed
when zero order forward mode is run for a ``base2ad`` result; e.g.
*af* below.
{xrst_literal
// BEGIN C++
// END C++
}
{xrst_end base2vec_ad.cpp}
*/
// BEGIN C++
# include <cppad/cppad.hpp>
bool base2vec_ad(void)
{ using CppAD::vector;
using CppAD::AD;
//
bool ok = true;
//
// f(x) = x[0] if 0 <= x[2] < 1
// = x[1] if 1 <= x[2] < 2
vector< AD<double> > ax(3), ay(1);
ax[0] = 3.0;
ax[1] = 2.0;
ax[2] = 1.0;
Independent(ax);
CppAD::VecAD<double> av(2);
av[ AD<double>(0) ] = ax[0];
av[ AD<double>(1) ] = ax[1];
ay[0] = av[ ax[2] ];
CppAD::ADFun<double> f(ax, ay);
//
// ok
// value during recording of f
ok &= ay[0] == ax[1];
//
// ok
// f zero order forward mode, the VecAD commands give expected result
vector<double> x(3), y(1);
x[0] = 2.0;
x[1] = 1.0;
x[2] = 0.0;
y = f.Forward(0, x);
ok &= y[0] == x[0];
//
// af
CppAD::ADFun< AD<double>, double > af = f.base2ad();
//
// g
ax[0] = 3.0;
ax[1] = 2.0;
ax[2] = 1.0;
Independent(ax);
ay = af.Forward(0, ax);
CppAD::ADFun<double> g(ax, ay);
//
// ok
// value during recording of g
ok &= ay[0] == ax[1];
//
// ok
// g zero order forward mode
// Note that this index does not change, but the value does
x[0] = 5.0;
x[1] = 4.0;
x[2] = 0.0;
y = g.Forward(0, x);
ok &= y[0] == x[1];
//
return ok;
}
// END C++
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