unitConversions.C

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-------------------------------------------------------------------------------
License
    This file is part of OpenFOAM.
 
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    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
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    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    for more details.
 
    You should have received a copy of the GNU General Public License
    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
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#include "unitConversions.H"
#include "demandDrivenData.H"
#include "dictionary.H"
 
using namespace Foam::constant::mathematical;
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
 
dictionary* unitsDictPtr_(nullptr);
 
const dictionary& unitsDict()
{
    if (!unitsDictPtr_)
    {
        dictionary* cachedPtr = nullptr;
 
        unitsDictPtr_ = new dictionary
        (
            debug::switchSet
            (
                debug::controlDict().found("UnitConversions")
              ? "UnitConversions"
              : debug::controlDict().found("DimensionSets")
              ? "DimensionSets"
              : "UnitConversions",
                cachedPtr
            )
        );
    }
 
    return *unitsDictPtr_;
}
 
HashTable<unitConversion>* addedUnitsPtr_(nullptr);
HashTable<unitConversion>* unitsPtr_(nullptr);
 
// Delete the above data at the end of the run
struct deleteUnitsPtr
{
    ~deleteUnitsPtr()
    {
        deleteDemandDrivenData(unitsDictPtr_);
        deleteDemandDrivenData(addedUnitsPtr_);
        deleteDemandDrivenData(unitsPtr_);
    }
};
 
deleteUnitsPtr deleteUnitsPtr_;
 
}
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
 
dimensionSet makeDimless()
{
    return dimensionSet(0, 0, 0, 0, 0);
}
 
unitConversion makeUnitless()
{
    return unitConversion(makeDimless(), 0, 0, 1);
}
 
unitConversion makeUnitAny()
{
    return unitConversion(makeDimless(), 0, 0, 0);
}
unitConversion makeUnitNone()
{
    return unitConversion(makeDimless(), 0, 0, -1);
}
 
unitConversion makeUnitFraction()
{
    return unitConversion(makeDimless(), 1, 0, 1);
}
unitConversion makeUnitPercent()
{
    return unitConversion(makeDimless(), 1, 0, 0.01);
}
 
unitConversion makeUnitRadians()
{
    return unitConversion(makeDimless(), 0, 1, 1);
}
unitConversion makeUnitRotations()
{
    return unitConversion(makeDimless(), 0, 1, 2*pi);
}
unitConversion makeUnitDegrees()
{
    return unitConversion(makeDimless(), 0, 1, pi/180);
}
 
}
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
const Foam::unitConversion Foam::unitless(makeUnitless());
 
const Foam::unitConversion Foam::unitAny(makeUnitAny());
const Foam::unitConversion Foam::unitNone(makeUnitNone());
 
const Foam::unitConversion Foam::unitFraction(makeUnitFraction());
const Foam::unitConversion Foam::unitPercent(makeUnitPercent());
 
const Foam::unitConversion Foam::unitRadians(makeUnitRadians());
const Foam::unitConversion Foam::unitRotations(makeUnitRotations());
const Foam::unitConversion Foam::unitDegrees(makeUnitDegrees());
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
Foam::scalar Foam::degToRad(const scalar deg)
{
    return unitDegrees.toStandard(deg);
}
 
 
Foam::scalar Foam::radToDeg(const scalar rad)
{
    return unitDegrees.toUser(rad);
}
 
 
void Foam::addUnits(const word& name, const unitConversion& units)
{
    deleteDemandDrivenData(unitsDictPtr_);
 
    if (!addedUnitsPtr_)
    {
        addedUnitsPtr_ = new HashTable<unitConversion>();
    }
 
    addedUnitsPtr_->insert(name, units);
 
    deleteDemandDrivenData(unitsPtr_);
}
 
 
const Foam::HashTable<Foam::unitConversion>& Foam::units()
{
    if (!unitsPtr_)
    {
        unitsPtr_ = new HashTable<unitConversion>();
 
        unitsPtr_->insert("%", makeUnitPercent());
 
        unitsPtr_->insert("rad", makeUnitRadians());
        unitsPtr_->insert("rot", makeUnitRotations());
        unitsPtr_->insert("deg", makeUnitDegrees());
 
        // Get the relevant part of the control dictionary
        const dictionary& unitSetDict =
            unitsDict().subDict(unitsDict().lookup<word>("unitSet") + "Coeffs");
 
        // Add units from the control dictionary
        forAllConstIter(dictionary, unitSetDict, iter)
        {
            ITstream& is = iter().stream();
 
            const unitConversion units(is);
            const scalar multiplier = pTraits<scalar>(is);
 
            const bool ok =
                unitsPtr_->insert
                (
                    iter().keyword(),
                    units*unitConversion(dimless, 0, 0, multiplier)
                );
 
            if (!ok)
            {
                FatalIOErrorInFunction(unitsDict())
                    << "Duplicate unit " << iter().keyword()
                    << " read from dictionary"
                    << exit(FatalIOError);
            }
        }
 
        // Add programmatically defined units
        if (addedUnitsPtr_)
        {
            forAllConstIter(HashTable<unitConversion>, *addedUnitsPtr_, iter)
            {
                const bool ok = unitsPtr_->insert(iter.key(), iter());
 
                if (!ok)
                {
                    FatalIOErrorInFunction(unitsDict())
                        << "Duplicate unit " << iter.key()
                        << " added to dictionary"
                        << exit(FatalIOError);
                }
            }
        }
    }
 
    return *unitsPtr_;
}
 
 
// ************************************************************************* //