ENH: Added new Function1: FunctionObjectValue

Returns a value retrieved from a function object result.

Usage:
    <entryName> functionObjectValue;
    <entryName>Coeffs
    {
        functionObject          <name>;
        functionObjectResult    <function object result field name>
    }

src/OpenFOAM/primitives/functions/Function1/FunctionObjectValue/FunctionObjectValue.C

+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2021 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    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/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "FunctionObjectValue.H"
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+template<class Type>
+void Foam::Function1Types::FunctionObjectValue<Type>::read
+(
+    const dictionary& coeffs
+)
+{
+    foName_ = coeffs.get<word>("functionObject");
+    foResultName_ = coeffs.get<word>("functionObjectResult");
+    haveDefaultValue_ = coeffs.readIfPresent("defaultValue", defaultValue_);
+}
+
+
+template<class Type>
+Foam::Function1Types::FunctionObjectValue<Type>::FunctionObjectValue
+(
+    const word& entryName,
+    const dictionary& dict,
+    const objectRegistry* obrPtr
+)
+:
+    Function1<Type>(entryName, dict, obrPtr),
+    foName_(),
+    foResultName_(),
+    defaultValue_(Zero),
+    haveDefaultValue_(false)
+{
+    read(dict);
+}
+
+
+template<class Type>
+Foam::Function1Types::FunctionObjectValue<Type>::FunctionObjectValue
+(
+    const FunctionObjectValue<Type>& rhs
+)
+:
+    Function1<Type>(rhs),
+    foName_(rhs.foName_),
+    foResultName_(rhs.foResultName_),
+    defaultValue_(rhs.defaultValue_),
+    haveDefaultValue_(rhs.haveDefaultValue_)
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template<class Type>
+void Foam::Function1Types::FunctionObjectValue<Type>::writeEntries
+(
+    Ostream& os
+) const
+{
+    os.writeEntry("functionObject", foName_);
+    os.writeEntry("functionObjectResult", foResultName_);
+
+    if (haveDefaultValue_)
+    {
+        os.writeEntry("defaultValue", defaultValue_);
+    }
+}
+
+
+template<class Type>
+void Foam::Function1Types::FunctionObjectValue<Type>::writeData
+(
+    Ostream& os
+) const
+{
+    Function1<Type>::writeData(os);
+    os.endEntry();
+
+    os.beginBlock(word(this->name() + "Coeffs"));
+    writeEntries(os);
+    os.endBlock();
+}
+
+
+// ************************************************************************* //

src/OpenFOAM/primitives/functions/Function1/FunctionObjectValue/FunctionObjectValue.H

+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2021 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    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/>.
+
+Class
+    Foam::Function1Types::FunctionObjectValue
+
+Description
+    Returns a value retrieved from a function object result.
+
+    Usage:
+    \verbatim
+        <entryName> functionObjectValue;
+        <entryName>Coeffs
+        {
+            functionObject          <name>;
+            functionObjectResult    <function object result field>;
+            defaultValue            <value>; // optional
+        }
+    \endverbatim
+
+
+Note
+- does not implement integrate()
+
+SourceFiles
+    FunctionObjectValue.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef Function1Types_FunctionObjectValue_H
+#define Function1Types_FunctionObjectValue_H
+
+#include "Function1.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace Function1Types
+{
+
+/*---------------------------------------------------------------------------*\
+                     Class FunctionObjectValue Declaration
+\*---------------------------------------------------------------------------*/
+
+template<class Type>
+class FunctionObjectValue
+:
+    public Function1<Type>
+{
+    // Private Data
+
+        //- Function object name
+        word foName_;
+
+        //- Function object result name
+        word foResultName_;
+
+        //- Default value when function object result is unavailable
+        Type defaultValue_;
+
+        //- Flag to indicate that default value is available
+        bool haveDefaultValue_;
+
+
+    // Private Member Functions
+
+        //- Read the coefficients from the given dictionary
+        void read(const dictionary& coeffs);
+
+
+public:
+
+    //- Runtime type information
+    TypeName("functionObjectValue");
+
+
+    // Generated Methods
+
+        //- No copy assignment
+        void operator=(const FunctionObjectValue<Type>&) = delete;
+
+
+    // Constructors
+
+        //- Construct from entry name, dictionary and optional registry
+        FunctionObjectValue
+        (
+            const word& entryName,
+            const dictionary& dict,
+            const objectRegistry* obrPtr = nullptr
+        );
+
+        //- Copy construct
+        explicit FunctionObjectValue(const FunctionObjectValue<Type>& rhs);
+
+        //- Construct and return a clone
+        virtual tmp<Function1<Type>> clone() const
+        {
+            return tmp<Function1<Type>>(new FunctionObjectValue<Type>(*this));
+        }
+
+
+    //- Destructor
+    virtual ~FunctionObjectValue() = default;
+
+
+    // Member Functions
+
+        //- Return value for time t
+        virtual inline Type value(const scalar t) const;
+
+        //- Integrate between two (scalar) values
+        virtual Type integrate(const scalar x1, const scalar x2) const;
+
+        //- Write in dictionary format
+        virtual void writeData(Ostream& os) const;
+
+        //- Write coefficient entries in dictionary format
+        void writeEntries(Ostream& os) const;
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Function1Types
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#include "FunctionObjectValueI.H"
+
+#ifdef NoRepository
+    #include "FunctionObjectValue.C"
+#endif
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //

src/OpenFOAM/primitives/functions/Function1/FunctionObjectValue/FunctionObjectValueI.H

+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2021 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    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/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "FunctionObjectValue.H"
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template<class Type>
+inline Type Foam::Function1Types::FunctionObjectValue<Type>::value
+(
+    const scalar /*unused*/
+) const
+{
+    const auto& props = this->time().functionObjects().propsDict();
+
+    if (!props.hasResultObject(foName_))
+    {
+        if (haveDefaultValue_)
+        {
+            Info<< "    Function object " << foName_
+                << " not found; using default value " << defaultValue_
+                << endl;
+
+            return defaultValue_;
+        }
+
+        FatalErrorInFunction
+            << "Function object " << foName_
+            << " results not found. Valid objects with results include: "
+            << props.objectResultNames()
+            << exit(FatalError);
+    }
+
+    if (!props.hasResultObjectEntry(foName_, foResultName_))
+    {
+        if (haveDefaultValue_)
+        {
+            Info<< "    Function object " << foName_
+                << " result " << foResultName_
+                << " not found; using default value " << defaultValue_
+                << endl;
+
+            return defaultValue_;
+        }
+
+        FatalErrorInFunction
+            << "Function object " << foName_
+            << " does not have a result field " << foResultName_ << nl
+            << " Available result fields include: "
+            << props.objectResultEntries(foName_)
+            << exit(FatalError);
+    }
+
+    Info<< "    Using " << foName_ << " function object value" << endl;
+
+    return props.template getObjectResult<Type>(foName_, foResultName_);
+}
+
+
+template<class Type>
+inline Type Foam::Function1Types::FunctionObjectValue<Type>::integrate
+(
+    const scalar x1,
+    const scalar x2
+) const
+{
+    NotImplemented;
+    return pTraits<Type>::zero;
+}
+
+
+// ************************************************************************* //

src/OpenFOAM/primitives/functions/Function1/makeFunction1s.C

@@ -39,6 +39,7 @@ License
 #include "TableFile.H"
 #include "Scale.H"
 #include "LimitRange.H"
+#include "FunctionObjectValue.H"
 #include "fieldTypes.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
@@ -57,7 +58,8 @@ License
     makeFunction1Type(Table, Type);                                            \
     makeFunction1Type(TableFile, Type);                                        \
     makeFunction1Type(Scale, Type);                                            \
-    makeFunction1Type(LimitRange, Type);
+    makeFunction1Type(LimitRange, Type);                                       \
+    makeFunction1Type(FunctionObjectValue, Type);
 
 #define makeFieldFunction1s(Type)                                              \
     makeFunction1(Type);                                                       \