src/gromacs/math/units.cpp

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  35 #include "gmxpre.h"
  36
  37 #include "units.h"
  38
  39 #include <cstdio>
  40
  41 #include "gromacs/utility/cstringutil.h"
  42
  43 double convert2gmx(double x, int unit)
  44 {
  45     switch (unit)
  46     {
  47         case eg2cAngstrom:
  48             return x*A2NM;
  49         case eg2cNm:
  50             return x;
  51         case eg2cBohr:
  52             return x*BOHR2NM;
  53         case eg2cKcal_Mole:
  54             return x/CAL2JOULE;
  55         case eg2cHartree:
  56             return x*ONE_4PI_EPS0/BOHR2NM;
  57         case eg2cHartree_e:
  58             return x*ONE_4PI_EPS0/BOHR2NM;
  59         case eg2cAngstrom3:
  60             return x*A2NM*A2NM*A2NM;
  61         case eg2cCoulomb:
  62             return x/E_CHARGE;
  63         case eg2cDebye:
  64             return x*DEBYE2ENM;
  65         case eg2cElectron:
  66             return x;
  67         case eg2cBuckingham:
  68             return x*A2NM*DEBYE2ENM;
  69         default:
  70             fprintf(stderr, "Unknown unit %d, not converting.\n", unit);
  71     }
  72     return x;
  73 }
  74
  75 double gmx2convert(double x, int unit)
  76 {
  77     switch (unit)
  78     {
  79         case eg2cAngstrom:
  80             return x/A2NM;
  81         case eg2cNm:
  82             return x;
  83         case eg2cBohr:
  84             return x/BOHR2NM;
  85         case eg2cKcal_Mole:
  86             return x*CAL2JOULE;
  87         case eg2cHartree:
  88             return x/(ONE_4PI_EPS0/BOHR2NM);
  89         case eg2cHartree_e:
  90             return x/(ONE_4PI_EPS0/BOHR2NM);
  91         case eg2cAngstrom3:
  92             return x/(A2NM*A2NM*A2NM);
  93         case eg2cCoulomb:
  94             return x*E_CHARGE;
  95         case eg2cDebye:
  96             return x/DEBYE2ENM;
  97         case eg2cElectron:
  98             return x;
  99         case eg2cBuckingham:
 100             return x/(A2NM*DEBYE2ENM);
 101         default:
 102             fprintf(stderr, "Unknown unit %d, not converting.\n", unit);
 103     }
 104     return x;
 105 }
 106
 107 /* This has to have the same order as the enums. */
 108 static const char *eg2c_names[eg2cNR] = {
 109     "Angstrom", "Nm", "Bohr", "Kcal_Mole",
 110     "Hartree", "Hartree_e", "Angstrom3", "Coulomb",
 111     "Debye", "Electron", "Buckingham"
 112 };
 113
 114 int string2unit(char *string)
 115 {
 116     int i;
 117
 118     for (i = 0; (i < eg2cNR); i++)
 119     {
 120         if (gmx_strcasecmp(string, eg2c_names[i]) == 0)
 121         {
 122             return i;
 123         }
 124     }
 125     return -1;
 126 }
 127
 128 const char *unit2string(int unit)
 129 {
 130     if ((unit >= 0) && (unit < eg2cNR))
 131     {
 132         return eg2c_names[unit];
 133     }
 134
 135     return nullptr;
 136 }