Line data    Source code

       1             : /* +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
       2             :    Copyright (c) 2013-2020 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 MCOLVAR DETERMINANT
      26             : /*
      27             : Calculate the determinant of a matrix
      28             : 
      29             : This shorctu allows you to calculate the [determinant](https://en.wikipedia.org/wiki/Determinant) of
      30             : a square matrix. The following example shows how the action is used:
      31             : 
      32             : ```plumed
      33             : d1: DISTANCE_MATRIX ATOMS=1-5
      34             : det: DETERMINANT ARG=d1
      35             : PRINT ARG=det FILE=colvar
      36             : ```
      37             : 
      38             : If you look at the expanded version of the input above you can see that PLUMED calculates the determinant
      39             : by first diagonalising the input matrix and then calculating the product of the eigenvalues.
      40             : 
      41             : */
      42             : //+ENDPLUMEDOC
      43             : 
      44             : namespace PLMD {
      45             : namespace matrixtools {
      46             : 
      47             : class Determinant : public ActionShortcut {
      48             : public:
      49             :   static void registerKeywords( Keywords& keys );
      50             :   explicit Determinant(const ActionOptions&ao);
      51             : };
      52             : 
      53             : PLUMED_REGISTER_ACTION(Determinant,"DETERMINANT")
      54             : 
      55           5 : void Determinant::registerKeywords( Keywords& keys ) {
      56           5 :   ActionShortcut::registerKeywords(keys);
      57          10 :   keys.addInputKeyword("compulsory","ARG","matrix","The matrix that we are calculating the determinant for");
      58          10 :   keys.setValueDescription("scalar","the determinant of the matrix");
      59           5 :   keys.needsAction("DIAGONALIZE");
      60           5 :   keys.needsAction("PRODUCT");
      61           5 : }
      62             : 
      63           1 : Determinant::Determinant( const ActionOptions& ao):
      64             :   Action(ao),
      65           1 :   ActionShortcut(ao) {
      66             :   std::string arg;
      67           1 :   parse("ARG",arg);
      68             :   // Compose a vector from the args
      69           2 :   readInputLine( getShortcutLabel() + "_diag: DIAGONALIZE ARG=" + arg + " VECTORS=all");
      70             :   // Not sure about the regexp here - check with matrix with more than 10 rows
      71           3 :   readInputLine( getShortcutLabel() + ": PRODUCT ARG=(" + getShortcutLabel() + R"=(_diag\.vals-[0-9]))=");
      72           1 : }
      73             : 
      74             : }
      75             : }