1 | // $Id: Poisson.cc 3615 2017-02-06 02:31:36Z peter $ |
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2 | |
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3 | /* |
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4 | Copyright (C) 2017 Peter Johansson |
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5 | |
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6 | This file is part of the yat library, http://dev.thep.lu.se/yat |
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7 | |
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8 | The yat library is free software; you can redistribute it and/or |
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9 | modify it under the terms of the GNU General Public License as |
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10 | published by the Free Software Foundation; either version 3 of the |
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11 | License, or (at your option) any later version. |
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12 | |
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13 | The yat library is distributed in the hope that it will be useful, |
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14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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16 | General Public License for more details. |
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17 | |
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18 | You should have received a copy of the GNU General Public License |
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19 | along with yat. If not, see <http://www.gnu.org/licenses/>. |
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20 | */ |
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21 | |
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22 | #include <config.h> |
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23 | |
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24 | #include "Poisson.h" |
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25 | |
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26 | #include <yat/utility/Matrix.h> |
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27 | #include <yat/utility/Vector.h> |
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28 | #include <yat/utility/VectorBase.h> |
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29 | #include <yat/utility/VectorConstView.h> |
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30 | |
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31 | #include <cassert> |
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32 | #include <cmath> |
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33 | |
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34 | namespace theplu { |
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35 | namespace yat { |
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36 | namespace regression { |
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37 | |
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38 | void Poisson::fit(const utility::Matrix& X, const utility::VectorBase& y) |
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39 | { |
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40 | assert(X.rows() == y.size()); |
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41 | beta_.resize(X.columns()+1); |
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42 | } |
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43 | |
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44 | |
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45 | const utility::Vector& Poisson::fit_parameters(void) const |
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46 | { |
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47 | return beta_; |
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48 | } |
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49 | |
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50 | |
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51 | double Poisson::predict(const utility::VectorBase& x) const |
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52 | { |
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53 | assert(x.size() + 1 == beta_.size()); |
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54 | using utility::VectorConstView; |
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55 | double logm = beta_(0) + VectorConstView(beta_, 1, x.size()) * x; |
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56 | return std::exp(logm); |
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57 | } |
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58 | |
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59 | }}} // of namespaces regression, yat, and theplu |
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