1 | /*---------------------------------------------------------------------------- |
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2 | ADOL-C -- Automatic Differentiation by Overloading in C++ |
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3 | File: tapeless_scalar.cpp |
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4 | Revision: $Id: tapeless_scalar.cpp 171 2010-10-04 13:57:19Z kulshres $ |
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5 | Contents: computation of coordinate transform, |
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6 | scalar tapeless forward mode |
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7 | described in the manual |
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8 | |
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9 | Copyright (c) Andrea Walther, Andreas Kowarz |
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10 | |
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11 | This file is part of ADOL-C. This software is provided as open source. |
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12 | Any use, reproduction, or distribution of the software constitutes |
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13 | recipient's acceptance of the terms of the accompanying license file. |
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14 | |
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15 | ---------------------------------------------------------------------------*/ |
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16 | |
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17 | |
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18 | /****************************************************************************/ |
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19 | /* INCLUDES */ |
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20 | |
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21 | #include <iostream> |
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22 | using namespace std; |
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23 | |
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24 | #define ADOLC_TAPELESS |
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25 | #include <adolc/adouble.h> |
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26 | typedef adtl::adouble adouble; |
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27 | |
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28 | |
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29 | int main(int argc, char *argv[]) { |
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30 | adouble x[3], y[3]; |
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31 | |
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32 | for (int i=0; i<3;++i) // Initialize x_i |
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33 | x[i] = i + 1.0; |
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34 | |
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35 | cout << endl << "Compute transform from Cartesian to spherical polar coordinates" << endl << endl; |
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36 | |
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37 | // derivative of y with respect to x0 |
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38 | x[0].setADValue(1); |
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39 | |
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40 | y[0] = sqrt(x[0]*x[0]+x[1]*x[1]+x[2]*x[2]); |
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41 | y[1] = atan(sqrt(x[0]*x[0]+x[1]*x[1])/x[2]); |
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42 | y[2] = atan(x[1]/x[0]); |
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43 | |
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44 | cout << "cartesian coordinates: " << endl; |
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45 | cout << "x[0] = " << x[0].getValue() << " x[1] = " << x[1].getValue() |
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46 | << " x[2] = " << x[2].getValue() << endl << endl; |
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47 | cout << "cpherical polar coordinates: " << endl; |
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48 | cout << "y[0] = " << y[0].getValue() << " y[1] = " << y[1].getValue() |
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49 | << " y[2] = " << y[2].getValue() << endl <<endl; |
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50 | |
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51 | // "use" the derivative |
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52 | cout << "derivative:" << endl; |
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53 | cout << "dy[0]/dx[0] = " << y[0].getADValue() << " dy[1]/dx[0] = " << y[1].getADValue() |
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54 | << " dy[2]/dx[0] = " << y[2].getADValue() << endl; |
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55 | |
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56 | return 0; |
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57 | } |
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58 | |
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