Using a User Defined AD Base Type: Example and Test
Keywords: using user defined ad base type: example test type purpose

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Using a User Defined AD Base Type: Example and Test
`

    # include "base_alloc.hpp"
    # include <cppad/cppad.hpp>

    bool base_require(void)
    {	bool ok = true;
    	using CppAD::thread_alloc;
    	typedef CppAD::AD<base_alloc> ad_base_alloc;

    	// check the amount of memory inuse by this thread (thread zero)
    	size_t thread = thread_alloc::thread_num();
    	ok &= thread == 0;

    	// y = x^2
    	size_t n = 1, m = 1;
    	CPPAD_TESTVECTOR(ad_base_alloc) a_x(n), a_y(m);
    	a_x[0] = ad_base_alloc(1.);
    	CppAD::Independent(a_x);
    	a_y[0] = a_x[0] * a_x[0];
    	CppAD::ADFun<base_alloc> f(a_x, a_y);

    	// check function value f(x) = x^2
    	CPPAD_TESTVECTOR(base_alloc) x(n), y(m);
    	base_alloc eps =
    		base_alloc(100.) * CppAD::numeric_limits<base_alloc>::epsilon();
    	x[0] = base_alloc(3.);
    	y    = f.Forward(0, x);
    	ok  &= CppAD::NearEqual(y[0], x[0] * x[0], eps, eps);

    	// check derivative value f'(x) = 2 * x
    	CPPAD_TESTVECTOR(base_alloc) dy(m * n);
    	dy   = f.Jacobian(x);
    	ok  &= CppAD::NearEqual(dy[0], base_alloc(2.) * x[0], eps, eps);

    	return ok;
    }

`
Purpose
The type `base_alloc`, defined in base_alloc.hpp , meets the requirements specified by base_require for `Base` in `AD<Base>` . The program below is an example use of `AD<base_alloc>` .

Input File: example/base_require.cpp