Line data    Source code

       1             : /* +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
       2             :    Copyright (c) 2017-2019 The plumed team
       3             :    (see the PEOPLE file at the root of the distribution for a list of names)
       4             : 
       5             :    See http://www.plumed.org for more information.
       6             : 
       7             :    This file is part of plumed, version 2.
       8             : 
       9             :    plumed is free software: you can redistribute it and/or modify
      10             :    it under the terms of the GNU Lesser General Public License as published by
      11             :    the Free Software Foundation, either version 3 of the License, or
      12             :    (at your option) any later version.
      13             : 
      14             :    plumed is distributed in the hope that it will be useful,
      15             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      16             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      17             :    GNU Lesser General Public License for more details.
      18             : 
      19             :    You should have received a copy of the GNU Lesser General Public License
      20             :    along with plumed.  If not, see <http://www.gnu.org/licenses/>.
      21             : +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */
      22             : #include "core/ActionRegister.h"
      23             : #include "core/ActionShortcut.h"
      24             : 
      25             : //+PLUMEDOC REWEIGHTING COVARIANCE_MATRIX
      26             : /*
      27             : Calculate a covariance matix
      28             : 
      29             : \par Examples
      30             : 
      31             : */
      32             : //+ENDPLUMEDOC
      33             : 
      34             : namespace PLMD {
      35             : namespace matrixtools {
      36             : 
      37             : class CovarianceMatrix : public ActionShortcut {
      38             : public:
      39             :   static void registerKeywords(Keywords&);
      40             :   explicit CovarianceMatrix(const ActionOptions&ao);
      41             : };
      42             : 
      43             : PLUMED_REGISTER_ACTION(CovarianceMatrix,"COVARIANCE_MATRIX")
      44             : 
      45          10 : void CovarianceMatrix::registerKeywords(Keywords& keys ) {
      46          10 :   ActionShortcut::registerKeywords( keys );
      47          20 :   keys.add("numbered","ARG","the vectors of data from which we are calculating the covariance");
      48          20 :   keys.add("compulsory","WEIGHTS","this keyword takes the label of an action that calculates a vector of values.  The elements of this vector "
      49             :            "are used as weights for the input data points.");
      50          20 :   keys.addFlag("UNORMALIZED",false,"do not divide by the sum of the weights");
      51          10 :   keys.setValueDescription("the covariance matrix");
      52          40 :   keys.needsAction("SUM"); keys.needsAction("CUSTOM"); keys.needsAction("VSTACK"); keys.needsAction("TRANSPOSE");
      53          30 :   keys.needsAction("ONES"); keys.needsAction("OUTER_PRODUCT"); keys.needsAction("MATRIX_PRODUCT");
      54          10 : }
      55             : 
      56           4 : CovarianceMatrix::CovarianceMatrix(const ActionOptions&ao):
      57             :   Action(ao),
      58           4 :   ActionShortcut(ao)
      59             : {
      60           8 :   std::vector<std::string> args; parseVector("ARG",args);
      61           4 :   unsigned nargs=args.size(); std::string argstr="ARG=" + args[0];
      62          12 :   for(unsigned i=1; i<args.size(); ++i) argstr += "," + args[i];
      63             : 
      64           8 :   bool unorm; parseFlag("UNORMALIZED",unorm); std::string wstr; parse("WEIGHTS",wstr);
      65           4 :   if( !unorm ) {
      66             :     // Normalize the weights
      67           8 :     readInputLine( getShortcutLabel() + "_wsum: SUM ARG=" + wstr + " PERIODIC=NO");
      68           8 :     readInputLine( getShortcutLabel() + "_weights: CUSTOM ARG=" + wstr + "," + getShortcutLabel() + "_wsum FUNC=x/y PERIODIC=NO");
      69           8 :     wstr = getShortcutLabel() + "_weights";
      70             :   }
      71             :   // Make a stack of all the data
      72           8 :   readInputLine( getShortcutLabel() + "_stack: VSTACK " + argstr );
      73             :   // And calculate the covariance matrix by first transposing the stack
      74           8 :   readInputLine( getShortcutLabel() + "_stackT: TRANSPOSE ARG=" + getShortcutLabel() + "_stack");
      75             :   // Create a matrix that holds all the weights
      76           4 :   std::string str_nargs; Tools::convert( nargs, str_nargs );
      77           8 :   readInputLine( getShortcutLabel() + "_ones: ONES SIZE=" + str_nargs );
      78             :   // Now create a matrix that holds all the weights
      79           8 :   readInputLine( getShortcutLabel() + "_matweights: OUTER_PRODUCT ARG=" + getShortcutLabel() + "_ones," + wstr );
      80             :   // And multiply the weights by the transpose to get the weighted transpose
      81           8 :   readInputLine( getShortcutLabel() + "_wT: CUSTOM ARG=" + getShortcutLabel() + "_matweights," + getShortcutLabel() + "_stackT FUNC=x*y PERIODIC=NO");
      82             :   // And now calculate the covariance by doing a suitable matrix product
      83           8 :   readInputLine( getShortcutLabel() + ": MATRIX_PRODUCT ARG=" + getShortcutLabel() + "_wT," + getShortcutLabel() + "_stack");
      84           4 : }
      85             : 
      86             : }
      87             : }