PLearn 0.1
IndexAtPositionVariable.cc
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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: IndexAtPositionVariable.cc 3994 2005-08-25 13:35:03Z chapados $
00040  * This file is part of the PLearn library.
00041  ******************************************************* */
00042 
00043 #include "IndexAtPositionVariable.h"
00044 #include "ColumnIndexVariable.h"
00045 
00046 namespace PLearn {
00047 using namespace std;
00048 
00049 
00052 PLEARN_IMPLEMENT_OBJECT(IndexAtPositionVariable,
00053                         "ONE LINE DESCR",
00054                         "NO HELP");
00055 
00056 
00057 IndexAtPositionVariable::IndexAtPositionVariable()
00058     : length_(0), width_(0)
00059 { }
00060   
00061 IndexAtPositionVariable::IndexAtPositionVariable(Variable* input1, Variable* input2, int the_length, int the_width)
00062     : inherited(input1, input2, the_length, the_width), length_(the_length), width_(the_width)
00063 {
00064     build_();
00065 }
00066 
00067 void
00068 IndexAtPositionVariable::build()
00069 {
00070     inherited::build();
00071     build_();
00072 }
00073 
00074 void
00075 IndexAtPositionVariable::build_()
00076 {
00077     if (input1 && input2) {
00078         if(!input1->isVec() || !input2->isVec())
00079             PLERROR("In IndexAtPositionVariable: input1 or input2 must be a vector var");
00080         if(input1->size() != input2->size() || input1->size() != width_)
00081             PLERROR("In IndexAtPositionVariable: input1 and input2 should be of same size");
00082     }
00083 }
00084 
00085 void
00086 IndexAtPositionVariable::declareOptions(OptionList &ol)
00087 {
00088     declareOption(ol, "length_", &IndexAtPositionVariable::length_, OptionBase::buildoption, "");
00089     declareOption(ol, "width_", &IndexAtPositionVariable::width_, OptionBase::buildoption, "");
00090     inherited::declareOptions(ol);
00091 }
00092 
00093 void IndexAtPositionVariable::recomputeSize(int& l, int& w) const
00094 { l=length_; w=width_; }
00095 
00096 
00097 void IndexAtPositionVariable::fprop()
00098 {
00099     value.clear();
00100     for (int j=0; j<input2->size(); j++)
00101     {  
00102         int i = (int)input2->valuedata[j];
00103         valuedata[i*width()+j] = input1->valuedata[j];
00104     }
00105 }
00106 
00107 
00108 void IndexAtPositionVariable::bprop()
00109 {
00110     for (int j=0; j<input2->size(); j++)
00111     {
00112         int i = (int)input2->valuedata[j];
00113         input1->gradientdata[i*width()+j] += gradientdata[j];
00114     }
00115 }
00116 
00117 
00118 void IndexAtPositionVariable::symbolicBprop()
00119 {
00120     input1->accg(new ColumnIndexVariable(g,input2));
00121 }
00122 
00123 
00124 void IndexAtPositionVariable::rfprop()
00125 {
00126 /*  if (rValue.length()==0) resizeRValue();
00127     rValue.clear();
00128     if (input2->isScalar()) // input2 is a scalar (interpreted as a k)
00129     {
00130     int k = (int)input2->valuedata[0];
00131     rvaluedata[k] = input1->rvaluedata[0];
00132     }
00133     else // input2 has 2 Indexs (interpreted as (i,j) coordinates)
00134     {
00135     int i = (int)input2->valuedata[0];
00136     int j = (int)input2->valuedata[1];
00137     rvaluedata[i*width()+j] = input1->rvaluedata[0];
00138     }*/
00139     PLERROR("IndexAtPositionVariable::rfprop() not implemented.");
00140 }
00141 
00142 
00143 
00144 } // end of namespace PLearn
00145 
00146 
00147 /*
00148   Local Variables:
00149   mode:c++
00150   c-basic-offset:4
00151   c-file-style:"stroustrup"
00152   c-file-offsets:((innamespace . 0)(inline-open . 0))
00153   indent-tabs-mode:nil
00154   fill-column:79
00155   End:
00156 */
00157 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=79 :
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