cantera/src/base/Units.cpp

466 lines
15 KiB
C++

//! @file Units.cpp
// This file is part of Cantera. See License.txt in the top-level directory or
// at https://cantera.org/license.txt for license and copyright information.
#include "cantera/base/Units.h"
#include "cantera/base/ctexceptions.h"
#include "cantera/base/global.h"
#include "cantera/base/stringUtils.h"
#include "cantera/base/AnyMap.h"
namespace {
using namespace Cantera;
const std::map<std::string, Units> knownUnits{
{"", Units(1.0)},
{"1", Units(1.0)},
// Mass [M]
{"kg", Units(1.0, 1, 0, 0)},
{"g", Units(1e-3, 1, 0, 0)},
// Length [L]
{"m", Units(1.0, 0, 1, 0)},
{"micron", Units(1e-6, 0, 1, 0)},
{"angstrom", Units(1e-10, 0, 1, 0)},
{"Å", Units(1e-10, 0, 1, 0)},
// Time [T]
{"s", Units(1.0, 0, 0, 1)},
{"min", Units(60, 0, 0, 1)},
{"hr", Units(3600, 0, 0, 1)},
// Temperature [K]
{"K", Units(1.0, 0, 0, 0, 1)},
{"C", Units(1.0, 0, 0, 0, 1)},
// Current [A]
{"A", Units(1.0, 0, 0, 0, 0, 1)},
// Quantity [Q]
{"mol", Units(1e-3, 0, 0, 0, 0, 0, 1)},
{"gmol", Units(1e-3, 0, 0, 0, 0, 0, 1)},
{"mole", Units(1e-3, 0, 0, 0, 0, 0, 1)},
{"kmol", Units(1.0, 0, 0, 0, 0, 0, 1)},
{"kgmol", Units(1.0, 0, 0, 0, 0, 0, 1)},
{"molec", Units(1.0/Avogadro, 0, 0, 0, 0, 0, 1)},
// Energy [M*L^2/T^2]
{"J", Units(1.0, 1, 2, -2)},
{"cal", Units(4.184, 1, 2, -2)},
{"erg", Units(1e-7, 1, 2, -2)},
{"eV", Units(ElectronCharge, 1, 2, -2)},
// Force [M*L/T^2]
{"N", Units(1.0, 1, 1, -2)},
{"dyn", Units(1e-5, 1, 1, -2)},
// Pressure [M/L/T^2]
{"Pa", Units(1.0, 1, -1, -2)},
{"atm", Units(OneAtm, 1, -1, -2)},
{"bar", Units(1.0e5, 1, -1, -2)},
{"dyn/cm^2", Units(0.1, 1, -1, -2)},
// Volume [L^3]
{"m^3", Units(1.0, 0, 3, 0)},
{"liter", Units(0.001, 0, 3, 0)},
{"L", Units(0.001, 0, 3, 0)},
{"l", Units(0.001, 0, 3, 0)},
{"cc", Units(1.0e-6, 0, 3, 0)},
// Other electrical units
{"ohm", Units(1.0, 1, 2, -3, 0, -2)}, // kg*m^2/s^3/A^2
{"V", Units(1.0, 1, 2, -3, 0, -1)}, // kg*m^2/s^3/A
{"coulomb", Units(1.0, 0, 0, 1, 0, 1)}, // A*s
//! Activation energy units [M*L^2/T^2/Q]
{"J/kmol", Units(1.0, 1, 2, -2, 0, 0, -1)},
};
const std::map<std::string, double> prefixes{
{"Y", 1e24},
{"Z", 1e21},
{"E", 1e18},
{"P", 1e15},
{"T", 1e12},
{"G", 1e9},
{"M", 1e6},
{"k", 1e3},
{"h", 1e2},
{"d", 1e-1},
{"c", 1e-2},
{"m", 1e-3},
{"u", 1e-6},
{"n", 1e-9},
{"p", 1e-12},
{"f", 1e-15},
{"a", 1e-18},
{"z", 1e-21},
{"y", 1e-24}
};
}
namespace Cantera
{
Units::Units(double factor, double mass, double length, double time,
double temperature, double current, double quantity)
: m_factor(factor)
, m_mass_dim(mass)
, m_length_dim(length)
, m_time_dim(time)
, m_temperature_dim(temperature)
, m_current_dim(current)
, m_quantity_dim(quantity)
, m_pressure_dim(0)
, m_energy_dim(0)
{
if (mass != 0 && length == -mass && time == -2 * mass
&& temperature == 0 && current == 0 && quantity == 0) {
// Dimension looks like Pa^n
m_pressure_dim = mass;
} else if (mass != 0 && length == 2 * mass && time == -2 * mass
&& temperature == 0 && current == 0 && quantity == 0)
{
// Dimesion looks like J^n
m_energy_dim = mass;
}
}
Units::Units(const std::string& name)
: m_factor(1.0)
, m_mass_dim(0)
, m_length_dim(0)
, m_time_dim(0)
, m_temperature_dim(0)
, m_current_dim(0)
, m_quantity_dim(0)
, m_pressure_dim(0)
, m_energy_dim(0)
{
size_t start = 0;
while (true) {
// Split into groups of the form 'unit^exponent'
size_t stop = name.find_first_of("*/", start);
size_t carat = name.find('^', start);
if (carat > stop) {
// No carat in this group
carat = npos;
}
std::string unit = trimCopy(
name.substr(start, std::min(carat, stop) - start));
double exponent = 1.0;
if (carat != npos) {
exponent = fpValueCheck(name.substr(carat+1, stop-carat-1));
}
if (start != 0 && name[start-1] == '/') {
// This unit is in the denominator
exponent = -exponent;
}
if (knownUnits.find(unit) != knownUnits.end()) {
// Incorporate the unit defined by the current group
*this *= knownUnits.at(unit).pow(exponent);
} else {
// See if the unit looks like a prefix + base unit
std::string prefix = unit.substr(0, 1);
std::string suffix = unit.substr(1);
if (prefixes.find(prefix) != prefixes.end() &&
knownUnits.find(suffix) != knownUnits.end()) {
Units u = knownUnits.at(suffix);
u.scale(prefixes.at(prefix));
*this *= u.pow(exponent);
} else {
throw CanteraError("Units::Units(string)",
"Unknown unit '{}' in unit string '{}'", unit, name);
}
}
start = stop+1;
if (stop == npos) {
break;
}
}
}
bool Units::convertible(const Units& other) const
{
return (m_mass_dim == other.m_mass_dim &&
m_length_dim == other.m_length_dim &&
m_time_dim == other.m_time_dim &&
m_temperature_dim == other.m_temperature_dim &&
m_current_dim == other.m_current_dim &&
m_quantity_dim == other.m_quantity_dim);
}
Units& Units::operator*=(const Units& other)
{
m_factor *= other.m_factor;
m_mass_dim += other.m_mass_dim;
m_length_dim += other.m_length_dim;
m_time_dim += other.m_time_dim;
m_temperature_dim += other.m_temperature_dim;
m_current_dim += other.m_current_dim;
m_quantity_dim += other.m_quantity_dim;
m_pressure_dim += other.m_pressure_dim;
m_energy_dim += other.m_energy_dim;
return *this;
}
Units Units::pow(double exponent) const {
return Units(std::pow(m_factor, exponent),
m_mass_dim * exponent,
m_length_dim * exponent,
m_time_dim * exponent,
m_temperature_dim * exponent,
m_current_dim * exponent,
m_quantity_dim * exponent);
}
std::string Units::str() const {
return fmt::format("Units({} kg^{} * m^{} * s^{} * K^{} * A^{} * kmol^{})",
m_factor, m_mass_dim, m_length_dim, m_time_dim,
m_temperature_dim, m_current_dim, m_quantity_dim);
}
UnitSystem::UnitSystem(std::initializer_list<std::string> units)
: m_mass_factor(1.0)
, m_length_factor(1.0)
, m_time_factor(1.0)
, m_pressure_factor(1.0)
, m_energy_factor(1.0)
, m_activation_energy_factor(1.0)
, m_quantity_factor(1.0)
, m_explicit_activation_energy(false)
{
setDefaults(units);
}
void UnitSystem::setDefaults(std::initializer_list<std::string> units)
{
for (const auto& name : units) {
auto unit = Units(name);
if (unit.convertible(knownUnits.at("kg"))) {
m_mass_factor = unit.factor();
} else if (unit.convertible(knownUnits.at("m"))) {
m_length_factor = unit.factor();
} else if (unit.convertible(knownUnits.at("s"))) {
m_time_factor = unit.factor();
} else if (unit.convertible(knownUnits.at("kmol"))) {
m_quantity_factor = unit.factor();
} else if (unit.convertible(knownUnits.at("Pa"))) {
m_pressure_factor = unit.factor();
} else if (unit.convertible(knownUnits.at("J"))) {
m_energy_factor = unit.factor();
} else if (unit.convertible(knownUnits.at("K"))
|| unit.convertible(knownUnits.at("A"))) {
// Do nothing -- no other scales are supported for temperature and current
} else {
throw CanteraError("UnitSystem::setDefaults",
"Unable to match unit '{}' to a basic dimension", name);
}
}
if (!m_explicit_activation_energy) {
m_activation_energy_factor = m_energy_factor / m_quantity_factor;
}
}
void UnitSystem::setDefaults(const std::map<std::string, std::string>& units)
{
for (const auto& item : units) {
auto& name = item.first;
Units unit(item.second);
if (name == "mass" && unit.convertible(knownUnits.at("kg"))) {
m_mass_factor = unit.factor();
} else if (name == "length" && unit.convertible(knownUnits.at("m"))) {
m_length_factor = unit.factor();
} else if (name == "time" && unit.convertible(knownUnits.at("s"))) {
m_time_factor = unit.factor();
} else if (name == "temperature" && item.second == "K") {
// do nothing - no other temperature scales are supported
} else if (name == "current" && item.second == "A") {
// do nothing - no other current scales are supported
} else if (name == "quantity" && unit.convertible(knownUnits.at("kmol"))) {
m_quantity_factor = unit.factor();
} else if (name == "pressure" && unit.convertible(knownUnits.at("Pa"))) {
m_pressure_factor = unit.factor();
} else if (name == "energy" && unit.convertible(knownUnits.at("J"))) {
m_energy_factor = unit.factor();
} else if (name == "activation-energy") {
// handled separately to allow override
} else {
throw CanteraError("UnitSystem::setDefaults",
"Unable to set default unit for '{}' to '{}' ({}).",
name, item.second, unit.str());
}
}
if (units.find("activation-energy") != units.end()) {
setDefaultActivationEnergy(units.at("activation-energy"));
} else if (!m_explicit_activation_energy) {
m_activation_energy_factor = m_energy_factor / m_quantity_factor;
}
}
void UnitSystem::setDefaultActivationEnergy(const std::string& e_units)
{
Units u(e_units);
if (u.convertible(Units("J/kmol"))) {
m_activation_energy_factor = u.factor();
} else if (u.convertible(knownUnits.at("K"))) {
m_activation_energy_factor = GasConstant;
} else if (u.convertible(knownUnits.at("eV"))) {
m_activation_energy_factor = u.factor() * Avogadro;
} else {
throw CanteraError("Units::setDefaultActivationEnergy",
"Unable to match unit '{}' to a unit of activation energy", e_units);
}
m_explicit_activation_energy = true;
}
double UnitSystem::convert(double value, const std::string& src,
const std::string& dest) const
{
return convert(value, Units(src), Units(dest));
}
double UnitSystem::convert(double value, const Units& src,
const Units& dest) const
{
if (!src.convertible(dest)) {
throw CanteraError("UnitSystem::convert",
"Incompatible units:\n {} and\n {}", src.str(), dest.str());
}
return value * src.factor() / dest.factor();
}
double UnitSystem::convert(double value, const std::string& dest) const
{
return convert(value, Units(dest));
}
double UnitSystem::convert(double value, const Units& dest) const
{
return value / dest.factor()
* pow(m_mass_factor, dest.m_mass_dim - dest.m_pressure_dim - dest.m_energy_dim)
* pow(m_length_factor, dest.m_length_dim + dest.m_pressure_dim - 2*dest.m_energy_dim)
* pow(m_time_factor, dest.m_time_dim + 2*dest.m_pressure_dim + 2*dest.m_energy_dim)
* pow(m_quantity_factor, dest.m_quantity_dim)
* pow(m_pressure_factor, dest.m_pressure_dim)
* pow(m_energy_factor, dest.m_energy_dim);
}
static std::pair<double, std::string> split_unit(const AnyValue& v) {
if (v.is<std::string>()) {
// Should be a value and units, separated by a space, e.g. '2e4 J/kmol'
std::string val_units = v.asString();
size_t space = val_units.find(" ");
if (space == npos) {
throw CanteraError("UnitSystem::convert",
"Couldn't parse '{}' as a space-separated value/unit pair\n",
val_units);
}
return {fpValueCheck(val_units.substr(0, space)),
val_units.substr(space+1)};
} else {
// Just a value
return {v.asDouble(), ""};
}
}
double UnitSystem::convert(const AnyValue& v, const std::string& dest) const
{
return convert(v, Units(dest));
}
double UnitSystem::convert(const AnyValue& v, const Units& dest) const
{
auto val_units = split_unit(v);
if (val_units.second.empty()) {
// Just a value, so convert using default units
return convert(val_units.first, dest);
} else {
// Both source and destination units are explicit
return convert(val_units.first, Units(val_units.second), dest);
}
}
vector_fp UnitSystem::convert(const std::vector<AnyValue>& vals,
const std::string& dest) const
{
return convert(vals, Units(dest));
}
vector_fp UnitSystem::convert(const std::vector<AnyValue>& vals,
const Units& dest) const
{
vector_fp out;
for (const auto& val : vals) {
out.emplace_back(convert(val, dest));
}
return out;
}
double UnitSystem::convertActivationEnergy(double value, const std::string& src,
const std::string& dest) const
{
// Convert to J/kmol
Units usrc(src);
if (usrc.convertible(Units("J/kmol"))) {
value *= usrc.factor();
} else if (usrc.convertible(Units("K"))) {
value *= GasConstant * usrc.factor();
} else if (usrc.convertible(Units("eV"))) {
value *= Avogadro * usrc.factor();
} else {
throw CanteraError("UnitSystem::convertActivationEnergy",
"Don't understand units '{}' as an activation energy", src);
}
// Convert from J/kmol
Units udest(dest);
if (udest.convertible(Units("J/kmol"))) {
value /= udest.factor();
} else if (udest.convertible(Units("K"))) {
value /= GasConstant * udest.factor();
} else if (udest.convertible(Units("eV"))) {
value /= Avogadro * udest.factor();
} else {
throw CanteraError("UnitSystem::convertActivationEnergy",
"Don't understand units '{}' as an activation energy", dest);
}
return value;
}
double UnitSystem::convertActivationEnergy(double value,
const std::string& dest) const
{
Units udest(dest);
if (udest.convertible(Units("J/kmol"))) {
return value * m_activation_energy_factor / udest.factor();
} else if (udest.convertible(knownUnits.at("K"))) {
return value * m_activation_energy_factor / GasConstant;
} else if (udest.convertible(knownUnits.at("eV"))) {
return value * m_activation_energy_factor / (Avogadro * udest.factor());
} else {
throw CanteraError("UnitSystem::convertActivationEnergy",
"'{}' is not a unit of activation energy", dest);
}
}
double UnitSystem::convertActivationEnergy(const AnyValue& v,
const std::string& dest) const
{
auto val_units = split_unit(v);
if (val_units.second.empty()) {
// Just a value, so convert using default units
return convertActivationEnergy(val_units.first, dest);
} else {
// Both source and destination units are explicit
return convertActivationEnergy(val_units.first, val_units.second, dest);
}
}
}