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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
// ----------------------------------------------------------------------------
/*
Old example, now used just for validation testing
*/
# include <cppad/cppad.hpp>
bool assign(void)
{ bool ok = true;
using CppAD::AD;
// domain space vector
size_t n = 3;
CPPAD_TESTVECTOR(AD<double>) x(n);
x[0] = 2; // AD<double> = int
x[1] = 3.; // AD<double> = double
x[2] = x[1]; // AD<double> = AD<double>
// declare independent variables and start tape recording
CppAD::Independent(x);
// range space vector
size_t m = 3;
CPPAD_TESTVECTOR(AD<double>) y(m);
// assign an AD<Base> object equal to an independent variable
// (choose the first independent variable to check a special case)
// use the value returned by the assignment (for another assignment)
y[0] = y[1] = x[0];
// assign an AD<Base> object equal to an expression
y[1] = x[1] + 1.;
y[2] = x[2] + 2.;
// check that all the resulting components of y depend on x
ok &= Variable(y[0]); // y[0] = x[0]
ok &= Variable(y[1]); // y[1] = x[1] + 1
ok &= Variable(y[2]); // y[2] = x[2] + 2
// construct f : x -> y and stop the tape recording
CppAD::ADFun<double> f(x, y);
// check variable values
ok &= ( y[0] == 2.);
ok &= ( y[1] == 4.);
ok &= ( y[2] == 5.);
// compute partials w.r.t x[1]
CPPAD_TESTVECTOR(double) dx(n);
CPPAD_TESTVECTOR(double) dy(m);
dx[0] = 0.;
dx[1] = 1.;
dx[2] = 0.;
dy = f.Forward(1, dx);
ok &= (dy[0] == 0.); // dy[0] / dx[1]
ok &= (dy[1] == 1.); // dy[1] / dx[1]
ok &= (dy[2] == 0.); // dy[2] / dx[1]
// compute the derivative y[2]
CPPAD_TESTVECTOR(double) w(m);
CPPAD_TESTVECTOR(double) dw(n);
w[0] = 0.;
w[1] = 0.;
w[2] = 1.;
dw = f.Reverse(1, w);
ok &= (dw[0] == 0.); // dy[2] / dx[0]
ok &= (dw[1] == 0.); // dy[2] / dx[1]
ok &= (dw[2] == 1.); // dy[2] / dx[2]
// assign a VecAD<Base>::reference
CppAD::VecAD<double> v(1);
AD<double> zero(0);
v[zero] = 5.;
ok &= (v[0] == 5.);
return ok;
}
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