src/gromacs/math/units.cpp

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