src/mdlib/calcmu.c

   1 /*
   2  *
   3  *                This source code is part of
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   5  *                 G   R   O   M   A   C   S
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   7  *          GROningen MAchine for Chemical Simulations
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   9  *                        VERSION 3.2.0
  10  * Written by David van der Spoel, Erik Lindahl, Berk Hess, and others.
  11  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
  12  * Copyright (c) 2001-2004, The GROMACS development team,
  13  * check out http://www.gromacs.org for more information.
  14
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License
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  35 /* This file is completely threadsafe - keep it that way! */
  36 #ifdef HAVE_CONFIG_H
  37 #include <config.h>
  38 #endif
  39
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include "typedefs.h"
  43 #include "network.h"
  44 #include "vec.h"
  45 #include "gmx_fatal.h"
  46 #include "physics.h"
  47 #include "main.h"
  48 #include "calcmu.h"
  49
  50 void calc_mu(int start,int homenr,rvec x[],real q[],real qB[],
  51              int nChargePerturbed,
  52              dvec mu,dvec mu_B)
  53 {
  54   int i,end,m;
  55
  56   end   = start + homenr;
  57
  58   clear_dvec(mu);
  59   for(i=start; (i<end); i++)
  60     for(m=0; (m<DIM); m++)
  61       mu[m] += q[i]*x[i][m];
  62
  63   for(m=0; (m<DIM); m++)
  64     mu[m] *= ENM2DEBYE;
  65
  66   if (nChargePerturbed) {
  67     clear_dvec(mu_B);
  68     for(i=start; (i<end); i++)
  69       for(m=0; (m<DIM); m++)
  70         mu_B[m] += qB[i]*x[i][m];
  71
  72     for(m=0; (m<DIM); m++)
  73       mu_B[m] *= ENM2DEBYE;
  74   } else {
  75     copy_dvec(mu,mu_B);
  76   }
  77 }
  78
  79 bool read_mu(FILE *fp,rvec mu,real *vol)
  80 {
  81   /* For backward compatibility */
  82   real mmm[4];
  83
  84   if (fread(mmm,(size_t)(4*sizeof(real)),1,fp) != 1)
  85     return FALSE;
  86
  87   copy_rvec(mmm,mu);
  88   *vol = mmm[3];
  89
  90   return TRUE;
  91 }
  92