ENH: support optional dimensionSet reading

src/OpenFOAM/dimensionSet/dimensionSet.C

@@ -113,7 +113,7 @@ Foam::dimensionSet::dimensionSet(const dimensionSet& ds)
 
 bool Foam::dimensionSet::dimensionless() const
 {
-    for (const scalar& val : exponents_)
+    for (const scalar val : exponents_)
     {
         // ie, mag(val) > smallExponent
         if ((val > smallExponent) || (val < -smallExponent))
@@ -126,13 +126,15 @@ bool Foam::dimensionSet::dimensionless() const
 }
 
 
-const Foam::FixedList<Foam::scalar,7>& Foam::dimensionSet::values() const
+const Foam::FixedList<Foam::scalar,7>&
+Foam::dimensionSet::values() const noexcept
 {
     return exponents_;
 }
 
 
-Foam::FixedList<Foam::scalar,7>& Foam::dimensionSet::values()
+Foam::FixedList<Foam::scalar,7>&
+Foam::dimensionSet::values() noexcept
 {
     return exponents_;
 }

src/OpenFOAM/dimensionSet/dimensionSet.H

@@ -28,10 +28,21 @@ Class
     Foam::dimensionSet
 
 Description
-    Dimension set for the base types.
+    Dimension set for the base types, which can be used to implement
+    rigorous dimension checking for algebraic manipulation.
 
-    This type may be used to implement rigorous dimension checking
+    The dimensions are specified in the following order
-    for algebraic manipulation.
+    (SI units for reference only):
+    \table
+        Property    | SI Description        | SI unit
+        MASS        | kilogram              | \c kg
+        LENGTH      | metre                 | \c m
+        TIME        | second                | \c s
+        TEMPERATURE | Kelvin                | \c K
+        MOLES       | mole                  | \c mol
+        CURRENT     | Ampere                | \c A
+        LUMINOUS_INTENSITY | Candela        | \c cd
+    \endtable
 
 SourceFiles
     dimensionSet.C
@@ -55,7 +66,7 @@ namespace Foam
 {
 
 // Forward Declarations
-
+class dictionary;
 class dimensionSet;
 class dimensionSets;
 
@@ -79,13 +90,13 @@ public:
         //- Enumeration for the dimension exponents
         enum dimensionType
         {
-            MASS,               //!< kilogram   kg
+            MASS,               //!< kilogram   \c kg
-            LENGTH,             //!< metre      m
+            LENGTH,             //!< metre      \c m
-            TIME,               //!< second     s
+            TIME,               //!< second     \c s
-            TEMPERATURE,        //!< Kelvin     K
+            TEMPERATURE,        //!< Kelvin     \c K
-            MOLES,              //!< mole       mol
+            MOLES,              //!< mole       \c mol
-            CURRENT,            //!< Ampere     A
+            CURRENT,            //!< Ampere     \c A
-            LUMINOUS_INTENSITY  //!< Candela    Cd
+            LUMINOUS_INTENSITY  //!< Candela    \c cd
         };
 
 
@@ -130,7 +141,7 @@ private:
 
             // Constructors
 
-                 tokeniser(Istream& is);
+                 explicit tokeniser(Istream& is);
 
 
             // Member Functions
@@ -154,8 +165,8 @@ private:
         };
 
 
-        //- Reset exponents to nearest integer if close to it. Used to
+        //- Reset exponents to nearest integer if close to it.
-        //  handle reading with insufficient precision.
+        //  Handles reading with insufficient precision.
         void round(const scalar tol);
 
         dimensionedScalar parse
@@ -165,6 +176,7 @@ private:
             const HashTable<dimensionedScalar>&
         ) const;
 
+
 public:
 
     // Declare name of the class and its debug switch
@@ -212,8 +224,22 @@ public:
         //- Copy construct
         dimensionSet(const dimensionSet& ds);
 
-        //- Construct from dictionary entry - usually "dimensions".
+        //- Construct from dictionary entry (usually "dimensions")
-        dimensionSet(const dictionary& dict, const word& entryName);
+        //  Dimensionless if non-mandatory and not found.
+        dimensionSet
+        (
+            const word& entryName,  //!< Lookup key. LITERAL (not REGEX)
+            const dictionary& dict,
+            const bool mandatory = true
+        );
+
+        //- Construct from dictionary entry (usually "dimensions")
+        dimensionSet
+        (
+            const dictionary& dict,
+            const word& entryName,  //!< Lookup key. LITERAL (not REGEX)
+            const bool mandatory = true
+        );
 
         //- Construct and return a clone
         autoPtr<dimensionSet> clone() const
@@ -230,13 +256,13 @@ public:
         //- Return true if it is dimensionless
         bool dimensionless() const;
 
-        //- Return const access to the exponents as a list
+        //- Const access to the exponents as a list
-        const FixedList<scalar,7>& values() const;
+        const FixedList<scalar,7>& values() const noexcept;
 
-        //- Return non-const access to the exponents as a list
+        //- Non-const access to the exponents as a list
-        FixedList<scalar,7>& values();
+        FixedList<scalar,7>& values() noexcept;
 
-        //- Reset exponents to be dimensionless
+        //- Clear exponents - resets to be dimensionless
         void clear();
 
         //- Copy assign the exponents from the dimensionSet
@@ -245,6 +271,18 @@ public:
 
     // IO
 
+        //- Update the dimensions from dictionary entry.
+        //- FatalIOError if it is found and the number of tokens is incorrect,
+        //- or it is mandatory and not found.
+        //
+        //  \return true if the entry was found.
+        bool readEntry
+        (
+            const word& entryName,      //!< Lookup key. LITERAL (not REGEX)
+            const dictionary& dict,     //!< The dictionary
+            const bool mandatory = true //!< The entry is mandatory
+        );
+
         //- Read using provided units. Used only in initial parsing
         Istream& read
         (
@@ -303,6 +341,7 @@ public:
         bool operator/=(const dimensionSet&);
 };
 
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 // IOstream Operators

src/OpenFOAM/dimensionSet/dimensionSetIO.C

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2015 OpenFOAM Foundation
-    Copyright (C) 2019 OpenCFD Ltd.
+    Copyright (C) 2019-2021 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -26,21 +26,37 @@ License
 
 \*---------------------------------------------------------------------------*/
 
+#include "dictionary.H"
 #include "dimensionSet.H"
-#include "IOstreams.H"
 #include "dimensionedScalar.H"
+#include "IOstreams.H"
 #include <limits>
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
-Foam::dimensionSet::dimensionSet(const dictionary& dict, const word& entryName)
+Foam::dimensionSet::dimensionSet
+(
+    const word& entryName,
+    const dictionary& dict,
+    const bool mandatory
+)
+:
+    exponents_(Zero)
 {
-    const entry& e = dict.lookupEntry(entryName, keyType::LITERAL);
+    this->readEntry(entryName, dict, mandatory);
-    ITstream& is = e.stream();
+}
 
-    is >> *this;
 
-    e.checkITstream(is);
+Foam::dimensionSet::dimensionSet
+(
+    const dictionary& dict,
+    const word& entryName,
+    const bool mandatory
+)
+:
+    exponents_(Zero)
+{
+    this->readEntry(entryName, dict, mandatory);
 }
 
 
@@ -122,26 +138,24 @@ bool Foam::dimensionSet::tokeniser::valid(char c)
 
 Foam::label Foam::dimensionSet::tokeniser::priority(const token& t)
 {
-    if (!t.isPunctuation())
+    if (t.isPunctuation())
     {
-        return 0;
+        if
-    }
+        (
-    else if
+            t.pToken() == token::MULTIPLY
-    (
+         || t.pToken() == token::DIVIDE
-        t.pToken() == token::MULTIPLY
+        )
-     || t.pToken() == token::DIVIDE
+        {
-    )
+            return 2;
-    {
+        }
-        return 2;
+        else if (t.pToken() == '^')
-    }
+        {
-    else if (t.pToken() == '^')
+            return 3;
-    {
+        }
-        return 3;
-    }
-    else
-    {
-        return 0;
     }
+
+    // Default priority
+    return 0;
 }
 
 
@@ -230,6 +244,8 @@ void Foam::dimensionSet::tokeniser::putBack(const token& t)
 }
 
 
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
 void Foam::dimensionSet::round(const scalar tol)
 {
     scalar integralPart;
@@ -260,7 +276,7 @@ Foam::dimensionedScalar Foam::dimensionSet::parse
     const HashTable<dimensionedScalar>& readSet
 ) const
 {
-    dimensionedScalar ds("", dimless, 1.0);
+    dimensionedScalar ds("", dimless, 1);
 
     // Get initial token
     token nextToken(tis.nextToken());
@@ -359,12 +375,12 @@ Foam::dimensionedScalar Foam::dimensionSet::parse
             {
                 if (nextPrior > lastPrior)
                 {
-                    dimensionedScalar exp(parse(nextPrior, tis, readSet));
+                    dimensionedScalar expon(parse(nextPrior, tis, readSet));
 
-                    ds.dimensions().reset(pow(ds.dimensions(), exp.value()));
+                    ds.dimensions().reset(pow(ds.dimensions(), expon.value()));
                     // Round to nearest integer if close to it
                     ds.dimensions().round(10*smallExponent);
-                    ds.value() = Foam::pow(ds.value(), exp.value());
+                    ds.value() = Foam::pow(ds.value(), expon.value());
                 }
                 else
                 {
@@ -409,6 +425,38 @@ Foam::dimensionedScalar Foam::dimensionSet::parse
 }
 
 
+bool Foam::dimensionSet::readEntry
+(
+    const word& entryName,
+    const dictionary& dict,
+    const bool mandatory
+)
+{
+    const entry* eptr = dict.findEntry(entryName, keyType::LITERAL);
+
+    if (eptr)
+    {
+        const entry& e = *eptr;
+        ITstream& is = e.stream();
+
+        is >> *this;
+
+        e.checkITstream(is);
+
+        return true;
+    }
+    else if (mandatory)
+    {
+        FatalIOErrorInFunction(dict)
+            << "Entry '" << entryName << "' not found in dictionary "
+            << dict.relativeName() << nl
+            << exit(FatalIOError);
+    }
+
+    return false;
+}
+
+
 Foam::Istream& Foam::dimensionSet::read
 (
     Istream& is,
@@ -533,7 +581,7 @@ Foam::Istream& Foam::dimensionSet::read
 
 
             // Parse unit
-            dimensionSet symbolSet(dimless);
+            dimensionSet symbolSet;  // dimless
 
             const auto index = symbolPow.find('^');
             if (index != std::string::npos)
@@ -542,7 +590,7 @@ Foam::Istream& Foam::dimensionSet::read
                 const scalar exponent = readScalar(symbolPow.substr(index+1));
 
                 dimensionedScalar s;
-                s.read(readSet.lookup(symbol), readSet);
+                s.read(readSet.lookup(symbol, keyType::LITERAL), readSet);
 
                 symbolSet.reset(pow(s.dimensions(), exponent));
 
@@ -553,7 +601,7 @@ Foam::Istream& Foam::dimensionSet::read
             else
             {
                 dimensionedScalar s;
-                s.read(readSet.lookup(symbolPow), readSet);
+                s.read(readSet.lookup(symbolPow, keyType::LITERAL), readSet);
 
                 symbolSet.reset(s.dimensions());
                 multiplier *= s.value();

src/OpenFOAM/dimensionSet/dimensionSets.C

@@ -186,7 +186,7 @@ const dimensionSets& writeUnitSet()
 }
 
 
-const dimensionSet dimless(0, 0, 0, 0, 0, 0, 0);
+const dimensionSet dimless;
 
 const dimensionSet dimMass(1, 0, 0, 0, 0, 0, 0);
 const dimensionSet dimLength(0, 1, 0, 0, 0, 0, 0);

src/OpenFOAM/dimensionSet/dimensionSets.H

@@ -34,7 +34,6 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-
 #ifndef dimensionSets_H
 #define dimensionSets_H
 
@@ -85,7 +84,7 @@ extern const dimensionSet dimDynamicViscosity;
 //- Construction of unit sets
 class dimensionSets
 {
-    // Private data
+    // Private Data
 
         //- Set of dimensions
         PtrList<dimensionedScalar> units_;
@@ -111,16 +110,17 @@ public:
             const wordList& unitNames
         );
 
+
     // Member Functions
 
         //- Return the units
-        const PtrList<dimensionedScalar>& units() const
+        const PtrList<dimensionedScalar>& units() const noexcept
         {
             return units_;
         }
 
         //- Is there a valid inverse of the selected unit
-        bool valid() const
+        bool valid() const noexcept
         {
             return valid_;
         }

src/OpenFOAM/dimensionedTypes/dimensionedScalar/dimensionedScalarFwd.H

@@ -39,8 +39,7 @@ namespace Foam
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
-template<class Type>
+template<class Type> class dimensioned;
-class dimensioned;
 
 typedef dimensioned<scalar> dimensionedScalar;
 

src/OpenFOAM/fields/DimensionedFields/DimensionedField/DimensionedFieldIO.C

@@ -38,7 +38,7 @@ void Foam::DimensionedField<Type, GeoMesh>::readField
     const word& fieldDictEntry
 )
 {
-    dimensions_.reset(dimensionSet(fieldDict, "dimensions"));
+    dimensions_.readEntry("dimensions", fieldDict);
 
     // Note: oriented state may have already been set on construction
     // - if so - do not reset by re-reading

src/OpenFOAM/fields/UniformDimensionedFields/UniformDimensionedField.C

@@ -85,8 +85,12 @@ template<class Type>
 bool Foam::UniformDimensionedField<Type>::readData(Istream& is)
 {
     dictionary dict(is);
-    scalar multiplier;
+    scalar multiplier(1);
-    this->dimensions().read(dict.lookup("dimensions"), multiplier);
+    this->dimensions().read
+    (
+        dict.lookup("dimensions", keyType::LITERAL),
+        multiplier
+    );
 
     dict.readEntry("value", this->value());
     this->value() *= multiplier;
@@ -98,7 +102,7 @@ bool Foam::UniformDimensionedField<Type>::readData(Istream& is)
 template<class Type>
 bool Foam::UniformDimensionedField<Type>::writeData(Ostream& os) const
 {
-    scalar multiplier;
+    scalar multiplier(1);
     os.writeKeyword("dimensions");
     this->dimensions().write(os, multiplier) << token::END_STATEMENT << nl;
     os.writeEntry("value", this->value()/multiplier) << nl;