1 | /* $Id: sub_zero.cpp 1370 2009-05-31 05:31:50Z bradbell $ */ |
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2 | /* -------------------------------------------------------------------------- |
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3 | CppAD: C++ Algorithmic Differentiation: Copyright (C) 2003-07 Bradley M. Bell |
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4 | |
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5 | CppAD is distributed under multiple licenses. This distribution is under |
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6 | the terms of the |
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7 | Common Public License Version 1.0. |
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8 | |
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9 | A copy of this license is included in the COPYING file of this distribution. |
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10 | Please visit http://www.coin-or.org/CppAD/ for information on other licenses. |
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11 | -------------------------------------------------------------------------- */ |
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12 | |
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13 | /* |
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14 | Test the use of the special parameters zero and one with the multiply operator |
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15 | */ |
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16 | |
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17 | # include <cppad/cppad.hpp> |
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18 | |
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19 | typedef CppAD::AD<double> ADdouble; |
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20 | typedef CppAD::AD< ADdouble > ADDdouble; |
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21 | |
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22 | bool SubZero(void) |
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23 | { |
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24 | using namespace CppAD; |
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25 | |
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26 | bool ok = true; |
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27 | |
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28 | size_t i; |
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29 | for(i = 0; i < 2; i++) |
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30 | { // run through the cases x = 0, 1 |
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31 | |
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32 | size_t j; |
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33 | for(j = 0; j < 2; j++) |
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34 | { // run through the cases y = 0, 1 |
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35 | |
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36 | CPPAD_TEST_VECTOR< ADdouble > x(1); |
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37 | x[0] = double(i); |
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38 | Independent(x); |
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39 | |
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40 | CPPAD_TEST_VECTOR< ADDdouble > y(1); |
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41 | y[0] = ADDdouble(j); |
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42 | Independent(y); |
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43 | |
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44 | CPPAD_TEST_VECTOR< ADDdouble > z(2); |
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45 | z[0] = x[0] - y[0]; |
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46 | z[1] = y[0] - x[0]; |
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47 | z[1] -= x[0]; |
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48 | |
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49 | // f(y) = z = { x - y , y - x - x } |
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50 | ADFun< ADdouble > f(y, z); |
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51 | CPPAD_TEST_VECTOR< ADdouble > u( f.Domain() ); |
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52 | CPPAD_TEST_VECTOR< ADdouble > v( f.Range() ); |
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53 | |
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54 | // v = f(y) |
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55 | u[0] = ADdouble(j); |
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56 | v = f.Forward(0, u); |
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57 | |
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58 | // check value of f |
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59 | ok &= v[0] == x[0] - ADdouble(j); |
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60 | ok &= v[1] == ADdouble(j) - x[0] - x[0]; |
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61 | |
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62 | // g(x) = f(y) = {x - y , y - x - x} |
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63 | ADFun<double> g(x, v); |
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64 | CPPAD_TEST_VECTOR< double > a( g.Domain() ); |
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65 | CPPAD_TEST_VECTOR< double > b( g.Range() ); |
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66 | |
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67 | // b = g'(x) |
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68 | a[0] = 1.; |
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69 | b = g.Forward(1, a); |
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70 | |
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71 | // check derivatives of g |
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72 | ok &= (b[0] == 1.); |
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73 | ok &= (b[1] == -2.); |
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74 | |
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75 | } |
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76 | } |
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77 | |
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78 | return ok; |
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79 | } |
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