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: ElementAtPositionVariable.cc 3994 2005-08-25 13:35:03Z chapados $ 00040 * This file is part of the PLearn library. 00041 ******************************************************* */ 00042 00043 #include "ElementAtPositionVariable.h" 00044 #include "VarElementVariable.h" 00045 00046 namespace PLearn { 00047 using namespace std; 00048 00049 00052 PLEARN_IMPLEMENT_OBJECT( 00053 ElementAtPositionVariable, 00054 "Indicator-like variable", 00055 "A variable of size length() x width(), filled with zeros except for the " 00056 "single element indexed by input2 =(i,j) or input2 = (k)."); 00057 00058 ElementAtPositionVariable::ElementAtPositionVariable() 00059 : length_(0), width_(0) 00060 { } 00061 00062 00063 ElementAtPositionVariable::ElementAtPositionVariable(Variable* input1, Variable* input2, int the_length, int the_width) 00064 : inherited(input1, input2, the_length, the_width), length_(the_length), width_(the_width) 00065 { 00066 build_(); 00067 } 00068 00069 void 00070 ElementAtPositionVariable::build() 00071 { 00072 inherited::build(); 00073 build_(); 00074 } 00075 00076 void 00077 ElementAtPositionVariable::build_() 00078 { 00079 if (input1 && !input1->isScalar()) 00080 PLERROR("In ElementAtPositionVariable: element must be a scalar var"); 00081 if (input2 && input2->nelems()>2) 00082 PLERROR("In ElementAtPositionVariable: position must have 1 or 2 elements"); 00083 } 00084 00085 void 00086 ElementAtPositionVariable::declareOptions(OptionList &ol) 00087 { 00088 declareOption(ol, "length_", &ElementAtPositionVariable::length_, OptionBase::buildoption, ""); 00089 declareOption(ol, "width_", &ElementAtPositionVariable::width_, OptionBase::buildoption, ""); 00090 inherited::declareOptions(ol); 00091 } 00092 00093 void ElementAtPositionVariable::recomputeSize(int& l, int& w) const 00094 { l=length_; w=width_; } 00095 00096 void ElementAtPositionVariable::fprop() 00097 { 00098 value.clear(); 00099 if (input2->isScalar()) // input2 is a scalar (interpreted as a k) 00100 { 00101 int k = (int)input2->valuedata[0]; 00102 valuedata[k] = input1->valuedata[0]; 00103 } 00104 else // input2 has 2 elements (interpreted as (i,j) coordinates) 00105 { 00106 int i = (int)input2->valuedata[0]; 00107 int j = (int)input2->valuedata[1]; 00108 valuedata[i*width()+j] = input1->valuedata[0]; 00109 } 00110 } 00111 00112 00113 void ElementAtPositionVariable::bprop() 00114 { 00115 if (input2->isScalar()) // input2 is a scalar (interpreted as a k) 00116 { 00117 int k = (int)input2->valuedata[0]; 00118 input1->gradientdata[0] += gradientdata[k]; 00119 } 00120 else // input2 has 2 elements (interpreted as (i,j) coordinates) 00121 { 00122 int i = (int)input2->valuedata[0]; 00123 int j = (int)input2->valuedata[1]; 00124 input1->gradientdata[0] += gradientdata[i*width()+j]; 00125 } 00126 } 00127 00128 00129 void ElementAtPositionVariable::symbolicBprop() 00130 { 00131 input1->accg(new VarElementVariable(g,input2)); 00132 } 00133 00134 00135 00136 void ElementAtPositionVariable::rfprop() 00137 { 00138 if (rValue.length()==0) resizeRValue(); 00139 rValue.clear(); 00140 if (input2->isScalar()) // input2 is a scalar (interpreted as a k) 00141 { 00142 int k = (int)input2->valuedata[0]; 00143 rvaluedata[k] = input1->rvaluedata[0]; 00144 } 00145 else // input2 has 2 elements (interpreted as (i,j) coordinates) 00146 { 00147 int i = (int)input2->valuedata[0]; 00148 int j = (int)input2->valuedata[1]; 00149 rvaluedata[i*width()+j] = input1->rvaluedata[0]; 00150 } 00151 } 00152 00153 00154 00155 } // end of namespace PLearn 00156 00157 00158 /* 00159 Local Variables: 00160 mode:c++ 00161 c-basic-offset:4 00162 c-file-style:"stroustrup" 00163 c-file-offsets:((innamespace . 0)(inline-open . 0)) 00164 indent-tabs-mode:nil 00165 fill-column:79 00166 End: 00167 */ 00168 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=79 :