PLearn 0.1
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00001 // -*- C++ -*- 00002 00003 // PLearn (A C++ Machine Learning Library) 00004 // Copyright (C) 1998 Pascal Vincent 00005 // Copyright (C) 1999-2002 Pascal Vincent, Yoshua Bengio, Rejean Ducharme and University of Montreal 00006 // Copyright (C) 2001-2002 Nicolas Chapados, Ichiro Takeuchi, Jean-Sebastien Senecal 00007 // Copyright (C) 2002 Xiangdong Wang, Christian Dorion 00008 00009 // Redistribution and use in source and binary forms, with or without 00010 // modification, are permitted provided that the following conditions are met: 00011 // 00012 // 1. Redistributions of source code must retain the above copyright 00013 // notice, this list of conditions and the following disclaimer. 00014 // 00015 // 2. Redistributions in binary form must reproduce the above copyright 00016 // notice, this list of conditions and the following disclaimer in the 00017 // documentation and/or other materials provided with the distribution. 00018 // 00019 // 3. The name of the authors may not be used to endorse or promote 00020 // products derived from this software without specific prior written 00021 // permission. 00022 // 00023 // THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR 00024 // IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 00025 // OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 00026 // NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 00027 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 00028 // TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 00029 // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 00030 // LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 00031 // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 00032 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00033 // 00034 // This file is part of the PLearn library. For more information on the PLearn 00035 // library, go to the PLearn Web site at www.plearn.org 00036 00037 00038 /* ******************************************************* 00039 * $Id: VarElementVariable.cc 8851 2008-04-21 20:53:25Z tihocan $ 00040 * This file is part of the PLearn library. 00041 ******************************************************* */ 00042 00043 #include "VarElementVariable.h" 00044 #include "ElementAtPositionVariable.h" 00045 00046 namespace PLearn { 00047 using namespace std; 00048 00049 00052 PLEARN_IMPLEMENT_OBJECT( 00053 VarElementVariable, 00054 "Variable that is the element of input1 indexed by input2.", 00055 "If input2 has 2 elements, it is interpreted as a (i,j) pair of indices\n" 00056 "in the matrix view of input1.\n" 00057 "If input2 is scalar, it is interpreted as the index in the vector view\n" 00058 "of input1." 00059 ); 00060 00062 // VarElementVariable // 00064 VarElementVariable::VarElementVariable(Variable* input1, Variable* input2, 00065 bool call_build_): 00066 inherited(input1, input2, 1, 1, call_build_) 00067 { 00068 if (call_build_) 00069 build_(); 00070 } 00071 00073 // build // 00075 void VarElementVariable::build() 00076 { 00077 inherited::build(); 00078 build_(); 00079 } 00080 00082 // build_ // 00084 void VarElementVariable::build_() 00085 { 00086 if (input2 && input2->nelems() > 2) 00087 PLERROR("IN VarElementVariable(Variable* input1, Variable* input2) input2 must have 1 (a k position index) or 2 elements (an i,j position index)"); 00088 } 00089 00090 void VarElementVariable::recomputeSize(int& l, int& w) const 00091 { l=1; w=1; } 00092 00093 void VarElementVariable::fprop() 00094 { 00095 if(input2->isScalar()) // scalar position index k 00096 { 00097 int k = int(input2->valuedata[0]); 00098 #ifdef BOUNDCHECK 00099 if (k >= input1->length() && k>= input1->width()) // we want to allow acces both to row vectors and column vectors. 00100 PLERROR("VarElementVariable::fprop() - k = %d is out of range (size is %d)", k, input1->length()); 00101 #endif 00102 valuedata[0] = input1->valuedata[k]; 00103 } 00104 else // (i,j) position index 00105 { 00106 int i = int(input2->valuedata[0]); 00107 int j = int(input2->valuedata[1]); 00108 #ifdef BOUNDCHECK 00109 if ((i * input1->width() + j) >= input1->width() * input1->length()) 00110 PLERROR("VarElementVariable::fprop() - (%d, %d) out of range" 00111 "(size is %d)", i, j, input1->length() * input1->width()); 00112 #endif 00113 valuedata[0] = input1->valuedata[i*input1->width()+j]; 00114 } 00115 } 00116 00117 00118 void VarElementVariable::bprop() 00119 { 00120 if(input2->isScalar()) // scalar position index k 00121 { 00122 int k = int(input2->valuedata[0]); 00123 input1->gradientdata[k] += gradientdata[0]; 00124 } 00125 else // (i,j) position index 00126 { 00127 int i = int(input2->valuedata[0]); 00128 int j = int(input2->valuedata[1]); 00129 input1->gradientdata[i*input1->width()+j] += gradientdata[0]; 00130 } 00131 } 00132 00133 00134 void VarElementVariable::symbolicBprop() 00135 { 00136 input1->accg(new ElementAtPositionVariable(g,input2,input1->length(),input1->width())); 00137 } 00138 00139 00140 void VarElementVariable::rfprop() 00141 { 00142 if (rValue.length()==0) resizeRValue(); 00143 if(input2->isScalar()) // scalar position index k 00144 { 00145 int k = int(input2->valuedata[0]); 00146 rvaluedata[0] = input1->rvaluedata[k]; 00147 } 00148 else // (i,j) position index 00149 { 00150 int i = int(input2->valuedata[0]); 00151 int j = int(input2->valuedata[1]); 00152 rvaluedata[0] = input1->rvaluedata[i*input1->width()+j]; 00153 } 00154 } 00155 00156 00157 00158 } // end of namespace PLearn 00159 00160 00161 /* 00162 Local Variables: 00163 mode:c++ 00164 c-basic-offset:4 00165 c-file-style:"stroustrup" 00166 c-file-offsets:((innamespace . 0)(inline-open . 0)) 00167 indent-tabs-mode:nil 00168 fill-column:79 00169 End: 00170 */ 00171 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=79 :