PLearn 0.1
RowAtPositionVariable.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: RowAtPositionVariable.cc 3994 2005-08-25 13:35:03Z chapados $
00040  * This file is part of the PLearn library.
00041  ******************************************************* */
00042 
00043 #include "RowAtPositionVariable.h"
00044 #include "VarRowVariable.h"
00045 
00046 namespace PLearn {
00047 using namespace std;
00048 
00049 
00052 PLEARN_IMPLEMENT_OBJECT(RowAtPositionVariable,
00053                         "Variables positionned inside a larger zero variable ...",
00054                         "NO HELP");
00055 
00056 RowAtPositionVariable::RowAtPositionVariable()
00057     : length_(-1)
00058 { }
00059   
00060 RowAtPositionVariable::RowAtPositionVariable(Variable* input1, Variable* input2, int the_length)
00061     : inherited(input1, input2, the_length, input1->width()), length_(the_length)
00062 {
00063     build_();
00064 }
00065 
00066 void
00067 RowAtPositionVariable::build()
00068 {
00069     inherited::build();
00070     build_();
00071 }
00072 
00073 void
00074 RowAtPositionVariable::build_()
00075 {
00076     if (input1 && input2) {
00077         if(!input1->isRowVec())
00078             PLERROR("In RowAtPositionVariable: input1 must be a single row");
00079         if(!input2->isScalar())
00080             PLERROR("In RowAtPositionVariable: position must be a scalar");
00081     }
00082 }
00083 
00084 void
00085 RowAtPositionVariable::declareOptions(OptionList &ol)
00086 {
00087     declareOption(ol, "length_", &RowAtPositionVariable::length_, OptionBase::buildoption, "");
00088     inherited::declareOptions(ol);
00089 }
00090 
00091 void RowAtPositionVariable::recomputeSize(int& l, int& w) const
00092 {
00093     l=length_;
00094     if (input1)
00095         w = input1->width();
00096     else
00097         w = 0;
00098 }
00099 
00100 void RowAtPositionVariable::fprop()
00101 {
00102     value.clear();
00103     int i = (int)input2->valuedata[0];
00104     matValue(i) << input1->value;
00105 }
00106 
00107 
00108 void RowAtPositionVariable::bprop()
00109 {
00110     int i = (int)input2->valuedata[0];
00111     input1->gradient += matGradient(i);
00112 }
00113 
00114 
00115 void RowAtPositionVariable::symbolicBprop()
00116 {
00117     input1->accg(new VarRowVariable(g,input2));
00118 }
00119 
00120 
00121 void RowAtPositionVariable::rfprop()
00122 {
00123     if (rValue.length()==0) resizeRValue();
00124     //rValue.clear();
00125     int i = (int)input2->valuedata[0];
00126     matRValue(i) << input1->rValue;
00127 }
00128 
00129 
00130 
00131 } // end of namespace PLearn
00132 
00133 
00134 /*
00135   Local Variables:
00136   mode:c++
00137   c-basic-offset:4
00138   c-file-style:"stroustrup"
00139   c-file-offsets:((innamespace . 0)(inline-open . 0))
00140   indent-tabs-mode:nil
00141   fill-column:79
00142   End:
00143 */
00144 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=79 :
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