diff --git a/src/physical_constants.c b/src/physical_constants.c
index d00d63df1c1e6a4821ce4ba50dfef9c4e0def9d2..b726678ec1c0f2c85e409da3898dc3b6b842750f 100644
--- a/src/physical_constants.c
+++ b/src/physical_constants.c
@@ -40,65 +40,68 @@ void phys_const_init(struct UnitSystem* us, struct phys_const* internal_const) {
const float dimension_G[5] = {-1, 3, -2, 0, 0};
internal_const->const_newton_G =
- const_newton_G_cgs / units_general_conversion_factor(us, dimension_G);
+ const_newton_G_cgs / units_general_cgs_conversion_factor(us, dimension_G);
const float dimension_c[5] = {0, 1, -1, 0, 0};
internal_const->const_speed_light_c =
const_speed_light_c_cgs /
- units_general_conversion_factor(us, dimension_c);
+ units_general_cgs_conversion_factor(us, dimension_c);
const float dimension_h[5] = {1, -2, -1, 0, 0};
internal_const->const_planck_h =
- const_planck_h_cgs / units_general_conversion_factor(us, dimension_h);
+ const_planck_h_cgs / units_general_cgs_conversion_factor(us, dimension_h);
internal_const->const_planck_hbar =
- const_planck_hbar_cgs / units_general_conversion_factor(us, dimension_h);
+ const_planck_hbar_cgs /
+ units_general_cgs_conversion_factor(us, dimension_h);
const float dimension_k[5] = {1, 2, -2, 0, -1};
internal_const->const_boltzmann_k =
- const_boltzmann_k_cgs / units_general_conversion_factor(us, dimension_k);
+ const_boltzmann_k_cgs /
+ units_general_cgs_conversion_factor(us, dimension_k);
const float dimension_thomson[5] = {0, 2, 0, 0, 0};
internal_const->const_thomson_cross_section =
const_thomson_cross_section_cgs /
- units_general_conversion_factor(us, dimension_thomson);
+ units_general_cgs_conversion_factor(us, dimension_thomson);
const float dimension_ev[5] = {1, 2, -2, 0, 0};
internal_const->const_electron_volt =
const_electron_volt_cgs /
- units_general_conversion_factor(us, dimension_ev);
+ units_general_cgs_conversion_factor(us, dimension_ev);
const float dimension_charge[5] = {0, 0, -1, 1, 0};
internal_const->const_electron_charge =
const_electron_charge_cgs /
- units_general_conversion_factor(us, dimension_charge);
+ units_general_cgs_conversion_factor(us, dimension_charge);
const float dimension_mass[5] = {1, 0, 0, 0, 0};
internal_const->const_electron_mass =
const_electron_mass_cgs /
- units_general_conversion_factor(us, dimension_mass);
+ units_general_cgs_conversion_factor(us, dimension_mass);
internal_const->const_proton_mass =
const_proton_mass_cgs /
- units_general_conversion_factor(us, dimension_mass);
+ units_general_cgs_conversion_factor(us, dimension_mass);
internal_const->const_solar_mass =
const_solar_mass_cgs /
- units_general_conversion_factor(us, dimension_mass);
+ units_general_cgs_conversion_factor(us, dimension_mass);
internal_const->const_earth_mass =
const_earth_mass_cgs /
- units_general_conversion_factor(us, dimension_mass);
+ units_general_cgs_conversion_factor(us, dimension_mass);
const float dimension_time[5] = {0, 0, 1, 0, 0};
internal_const->const_year =
- const_year_cgs / units_general_conversion_factor(us, dimension_time);
+ const_year_cgs / units_general_cgs_conversion_factor(us, dimension_time);
const float dimension_length[5] = {0, 1, 0, 0, 0};
internal_const->const_astronomical_unit =
const_astronomical_unit_cgs /
- units_general_conversion_factor(us, dimension_length);
+ units_general_cgs_conversion_factor(us, dimension_length);
internal_const->const_parsec =
- const_parsec_cgs / units_general_conversion_factor(us, dimension_length);
+ const_parsec_cgs /
+ units_general_cgs_conversion_factor(us, dimension_length);
internal_const->const_light_year =
const_light_year_cgs /
- units_general_conversion_factor(us, dimension_length);
+ units_general_cgs_conversion_factor(us, dimension_length);
}
void phys_const_print(struct phys_const* internal_const) {
diff --git a/src/units.c b/src/units.c
index 8e0ff08f1d92f47afbf44366acef7038fc8675c5..123725a856e33f4e2ba7c75766794c189736b057 100644
--- a/src/units.c
+++ b/src/units.c
@@ -90,10 +90,10 @@ double units_get_base_unit(const struct UnitSystem* us,
}
/**
- * @brief Returns the base unit symbol
+ * @brief Returns the base unit symbol used internally
* @param baseUnit The base unit
*/
-const char* units_get_base_unit_symbol(enum BaseUnits baseUnit) {
+const char* units_get_base_unit_internal_symbol(enum BaseUnits baseUnit) {
switch (baseUnit) {
case UNIT_MASS:
return "U_M";
@@ -115,7 +115,7 @@ const char* units_get_base_unit_symbol(enum BaseUnits baseUnit) {
* @brief Returns the base unit symbol in the cgs system
* @param baseUnit The base unit
*/
-const char* units_get_base_unit_CGS_symbol(enum BaseUnits baseUnit) {
+const char* units_get_base_unit_cgs_symbol(enum BaseUnits baseUnit) {
switch (baseUnit) {
case UNIT_MASS:
return "g";
@@ -275,13 +275,13 @@ void units_get_base_unit_exponants_array(float baseUnitsExp[5],
* @param us The system of units in use
* @param unit The unit to convert
*/
-double units_conversion_factor(const struct UnitSystem* us,
- enum UnitConversionFactor unit) {
+double units_cgs_conversion_factor(const struct UnitSystem* us,
+ enum UnitConversionFactor unit) {
float baseUnitsExp[5] = {0.f};
units_get_base_unit_exponants_array(baseUnitsExp, unit);
- return units_general_conversion_factor(us, baseUnitsExp);
+ return units_general_cgs_conversion_factor(us, baseUnitsExp);
}
/**
@@ -316,13 +316,13 @@ float units_a_factor(const struct UnitSystem* us,
* @brief Returns a string containing the exponents of the base units making up
* the conversion factors
*/
-void units_conversion_string(char* buffer, const struct UnitSystem* us,
- enum UnitConversionFactor unit) {
+void units_cgs_conversion_string(char* buffer, const struct UnitSystem* us,
+ enum UnitConversionFactor unit) {
float baseUnitsExp[5] = {0.f};
units_get_base_unit_exponants_array(baseUnitsExp, unit);
- units_general_conversion_string(buffer, us, baseUnitsExp);
+ units_general_cgs_conversion_string(buffer, us, baseUnitsExp);
}
/**
@@ -332,8 +332,8 @@ void units_conversion_string(char* buffer, const struct UnitSystem* us,
* @param baseUnitsExponants The exponent of each base units required to form
* the desired quantity. See conversionFactor() for a working example
*/
-double units_general_conversion_factor(const struct UnitSystem* us,
- const float baseUnitsExponants[5]) {
+double units_general_cgs_conversion_factor(const struct UnitSystem* us,
+ const float baseUnitsExponants[5]) {
double factor = 1.;
int i;
@@ -386,8 +386,9 @@ float units_general_a_factor(const struct UnitSystem* us,
* @param baseUnitsExponants The exponent of each base units required to form
* the desired quantity. See conversionFactor() for a working example
*/
-void units_general_conversion_string(char* buffer, const struct UnitSystem* us,
- const float baseUnitsExponants[5]) {
+void units_general_cgs_conversion_string(char* buffer,
+ const struct UnitSystem* us,
+ const float baseUnitsExponants[5]) {
char temp[14];
double a_exp = units_general_a_factor(us, baseUnitsExponants);
double h_exp = units_general_h_factor(us, baseUnitsExponants);
@@ -430,12 +431,12 @@ void units_general_conversion_string(char* buffer, const struct UnitSystem* us,
if (baseUnitsExponants[i] == 0.)
sprintf(temp, " ");
else if (baseUnitsExponants[i] == 1.)
- sprintf(temp, "%s ", units_get_base_unit_symbol(i));
+ sprintf(temp, "%s ", units_get_base_unit_internal_symbol(i));
else if (remainder(baseUnitsExponants[i], 1.) == 0)
- sprintf(temp, "%s^%d ", units_get_base_unit_symbol(i),
+ sprintf(temp, "%s^%d ", units_get_base_unit_internal_symbol(i),
(int)baseUnitsExponants[i]);
else
- sprintf(temp, "%s^%7.4f ", units_get_base_unit_symbol(i),
+ sprintf(temp, "%s^%7.4f ", units_get_base_unit_internal_symbol(i),
baseUnitsExponants[i]);
strncat(buffer, temp, 12);
}
@@ -448,12 +449,12 @@ void units_general_conversion_string(char* buffer, const struct UnitSystem* us,
if (baseUnitsExponants[i] == 0.)
continue;
else if (baseUnitsExponants[i] == 1.)
- sprintf(temp, "%s ", units_get_base_unit_CGS_symbol(i));
+ sprintf(temp, "%s ", units_get_base_unit_cgs_symbol(i));
else if (remainder(baseUnitsExponants[i], 1.) == 0)
- sprintf(temp, "%s^%d ", units_get_base_unit_CGS_symbol(i),
+ sprintf(temp, "%s^%d ", units_get_base_unit_cgs_symbol(i),
(int)baseUnitsExponants[i]);
else
- sprintf(temp, "%s^%7.4f ", units_get_base_unit_CGS_symbol(i),
+ sprintf(temp, "%s^%7.4f ", units_get_base_unit_cgs_symbol(i),
baseUnitsExponants[i]);
strncat(buffer, temp, 12);
}
@@ -461,3 +462,59 @@ void units_general_conversion_string(char* buffer, const struct UnitSystem* us,
strncat(buffer, "]", 2);
}
+
+/**
+ * @brief Are the two unit systems equal ?
+ *
+ * @param a The First #UnitSystem
+ * @param b The second #UnitSystem
+ * @return 1 if the systems are the same, 0 otherwise
+ */
+int units_are_equal(const struct UnitSystem* a, const struct UnitSystem* b) {
+
+ if (a->UnitMass_in_cgs != b->UnitMass_in_cgs) return 0;
+ if (a->UnitLength_in_cgs != b->UnitLength_in_cgs) return 0;
+ if (a->UnitTime_in_cgs != b->UnitTime_in_cgs) return 0;
+ if (a->UnitCurrent_in_cgs != b->UnitCurrent_in_cgs) return 0;
+ if (a->UnitTemperature_in_cgs != b->UnitTemperature_in_cgs) return 0;
+
+ return 1;
+}
+
+/**
+ * @brief Return the unit conversion factor between two systems
+ *
+ * @param from The #UnitSystem we are converting from
+ * @param to The #UnitSystem we are converting to
+ * @param baseUnitsExponants The exponent of each base units required to form
+ * the desired quantity. See conversionFactor() for a working example
+ */
+double units_general_conversion_factor(const struct UnitSystem* from,
+ const struct UnitSystem* to,
+ const float baseUnitsExponants[5]) {
+
+ const double from_cgs =
+ units_general_cgs_conversion_factor(from, baseUnitsExponants);
+ const double to_cgs =
+ units_general_cgs_conversion_factor(to, baseUnitsExponants);
+
+ return from_cgs / to_cgs;
+}
+
+/**
+ * @brief Return the unit conversion factor between two systems
+ *
+ * @param from The #UnitSystem we are converting from
+ * @param to The #UnitSystem we are converting to
+ * @return unit The unit we are converting
+ */
+double units_conversion_factor(const struct UnitSystem* from,
+ const struct UnitSystem* to,
+ enum UnitConversionFactor unit) {
+
+ float baseUnitsExp[5] = {0.f};
+
+ units_get_base_unit_exponants_array(baseUnitsExp, unit);
+
+ return units_general_conversion_factor(from, to, baseUnitsExp);
+}
diff --git a/src/units.h b/src/units.h
index 24e37e177480d7f84e41df1b73e2036aa00b7220..29b4563163b4fe224c881b1c1055f2cbfbcc95a1 100644
--- a/src/units.h
+++ b/src/units.h
@@ -94,13 +94,14 @@ enum UnitConversionFactor {
void units_init(struct UnitSystem*, const struct swift_params*,
const char* category);
+int units_are_equal(const struct UnitSystem* a, const struct UnitSystem* b);
+
+/* Base units */
double units_get_base_unit(const struct UnitSystem*, enum BaseUnits);
-const char* units_get_base_unit_symbol(enum BaseUnits);
-const char* units_get_base_unit_CGS_symbol(enum BaseUnits);
-double units_general_conversion_factor(const struct UnitSystem* us,
- const float baseUnitsExponants[5]);
-double units_conversion_factor(const struct UnitSystem* us,
- enum UnitConversionFactor unit);
+const char* units_get_base_unit_internal_symbol(enum BaseUnits);
+const char* units_get_base_unit_cgs_symbol(enum BaseUnits);
+
+/* Cosmology factors */
float units_general_h_factor(const struct UnitSystem* us,
const float baseUnitsExponants[5]);
float units_h_factor(const struct UnitSystem* us,
@@ -109,9 +110,24 @@ float units_general_a_factor(const struct UnitSystem* us,
const float baseUnitsExponants[5]);
float units_a_factor(const struct UnitSystem* us,
enum UnitConversionFactor unit);
-void units_general_conversion_string(char* buffer, const struct UnitSystem* us,
- const float baseUnitsExponants[5]);
-void units_conversion_string(char* buffer, const struct UnitSystem* us,
- enum UnitConversionFactor unit);
+
+/* Conversion to CGS */
+double units_general_cgs_conversion_factor(const struct UnitSystem* us,
+ const float baseUnitsExponants[5]);
+double units_cgs_conversion_factor(const struct UnitSystem* us,
+ enum UnitConversionFactor unit);
+void units_general_cgs_conversion_string(char* buffer,
+ const struct UnitSystem* us,
+ const float baseUnitsExponants[5]);
+void units_cgs_conversion_string(char* buffer, const struct UnitSystem* us,
+ enum UnitConversionFactor unit);
+
+/* Conversion between systems */
+double units_general_conversion_factor(const struct UnitSystem* from,
+ const struct UnitSystem* to,
+ const float baseUnitsExponants[5]);
+double units_conversion_factor(const struct UnitSystem* from,
+ const struct UnitSystem* to,
+ enum UnitConversionFactor unit);
#endif /* SWIFT_UNITS_H */