The AD log10 Function: Example and Test
Keywords: the ad log10 function: example test

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The AD log10 Function: Example and Test
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    # include <cppad/cppad.hpp>

    bool log10(void)
    {	bool ok = true;

    	using CppAD::AD;
    	using CppAD::NearEqual;

    	// domain space vector
    	size_t n  = 1;
    	double x0 = 0.5;
    	CPPAD_TESTVECTOR(AD<double>) x(n);
    	x[0]      = x0;

    	// declare independent variables and start tape recording
    	CppAD::Independent(x);

    	// ten raised to the x0 power
    	AD<double> ten = 10.;
    	AD<double> pow_10_x0 = CppAD::pow(ten, x[0]);

    	// range space vector
    	size_t m = 1;
    	CPPAD_TESTVECTOR(AD<double>) y(m);
    	y[0] = CppAD::log10(pow_10_x0);

    	// create f: x -> y and stop tape recording
    	CppAD::ADFun<double> f(x, y);

    	// check value
    	ok &= NearEqual(y[0] , x0,  1e-10 , 1e-10);

    	// forward computation of first partial w.r.t. x[0]
    	CPPAD_TESTVECTOR(double) dx(n);
    	CPPAD_TESTVECTOR(double) dy(m);
    	dx[0] = 1.;
    	dy    = f.Forward(1, dx);
    	ok   &= NearEqual(dy[0], 1., 1e-10, 1e-10);

    	// reverse computation of derivative of y[0]
    	CPPAD_TESTVECTOR(double)  w(m);
    	CPPAD_TESTVECTOR(double) dw(n);
    	w[0]  = 1.;
    	dw    = f.Reverse(1, w);
    	ok   &= NearEqual(dw[0], 1., 1e-10, 1e-10);

    	// use a VecAD<Base>::reference object with log10
    	CppAD::VecAD<double> v(1);
    	AD<double> zero(0);
    	v[zero]           = pow_10_x0;
    	AD<double> result = CppAD::log10(v[zero]);
    	ok   &= NearEqual(result, x0, 1e-10, 1e-10);

    	return ok;
    }

`

Input File: example/log10.cpp