ENH: cachedRandom: added support for global random numbers

src/OpenFOAM/primitives/random/cachedRandom/cachedRandom.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2013 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -25,6 +25,7 @@ License
 
 #include "cachedRandom.H"
 #include "OSspecific.H"
+#include "PstreamReduceOps.H"
 
 // * * * * * * * * * * * * * private Member Functions  * * * * * * * * * * * //
 
@@ -142,6 +143,78 @@ Foam::scalar Foam::cachedRandom::position
 }
 
 
+template<>
+Foam::label Foam::cachedRandom::globalSample01()
+{
+    scalar value = -GREAT;
+
+    if (Pstream::master())
+    {
+        value = scalar01();
+    }
+
+    reduce(value, maxOp<scalar>());
+
+    return round(value);
+}
+
+
+template<>
+Foam::scalar Foam::cachedRandom::globalSample01()
+{
+    scalar value = -GREAT;
+
+    if (Pstream::master())
+    {
+        value = scalar01();
+    }
+
+    reduce(value, maxOp<scalar>());
+
+    return value;
+}
+
+
+template<>
+Foam::label Foam::cachedRandom::globalPosition
+(
+    const label& start,
+    const label& end
+)
+{
+    label value = labelMin;
+
+    if (Pstream::master())
+    {
+        value = round(scalar01()*(end - start));
+    }
+
+    reduce(value, maxOp<label>());
+
+    return start + value;
+}
+
+
+template<>
+Foam::scalar Foam::cachedRandom::globalPosition
+(
+    const scalar& start,
+    const scalar& end
+)
+{
+    scalar value = -GREAT;
+
+    if (Pstream::master())
+    {
+        value = scalar01()*(end - start);
+    }
+
+    reduce(value, maxOp<scalar>());
+
+    return start + value;
+}
+
+
 void Foam::cachedRandom::operator=(const cachedRandom& cr)
 {
     seed_ = cr.seed_;

src/OpenFOAM/primitives/random/cachedRandom/cachedRandom.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2013 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -121,17 +121,33 @@ public:
 
         // Evaluation
 
-            //- Return a sample whose components lie in the range 0-1
-            template<class Type>
-            Type sample01();
+            // Random numbers
+                //- Return a sample whose components lie in the range 0-1
+                template<class Type>
+                Type sample01();
 
-            //- Return a sample between start and end
-            template<class Type>
-            Type position(const Type& start, const Type& end);
+                //- Return a sample between start and end
+                template<class Type>
+                Type position(const Type& start, const Type& end);
 
-            //- Randomise value in the range 0-1
-            template<class Type>
-            void randomise01(Type& value);
+                //- Randomise value in the range 0-1
+                template<class Type>
+                void randomise01(Type& value);
+
+
+            // Global random numbers - consistent across all processors
+
+                //- Return a sample whose components lie in the range 0-1
+                template<class Type>
+                Type globalSample01();
+
+                //- Return a sample between start and end
+                template<class Type>
+                Type globalPosition(const Type& start, const Type& end);
+
+                //- Randomise value in the range 0-1
+                template<class Type>
+                void globalRandomise01(Type& value);
 
 
         // Operators
@@ -160,6 +176,22 @@ scalar cachedRandom::position<scalar>
     const scalar& end
 );
 
+template<>
+label cachedRandom::globalSample01<label>();
+
+template<>
+scalar cachedRandom::globalSample01<scalar>();
+
+template<>
+label cachedRandom::globalPosition<label>(const label& start, const label& end);
+
+template<>
+scalar cachedRandom::globalPosition<scalar>
+(
+    const scalar& start,
+    const scalar& end
+);
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 } // End namespace Foam

src/OpenFOAM/primitives/random/cachedRandom/cachedRandomTemplates.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2013 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -24,6 +24,7 @@ License
 \*---------------------------------------------------------------------------*/
 
 #include "cachedRandom.H"
+#include "Pstream.H"
 
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
@@ -61,4 +62,50 @@ void Foam::cachedRandom::randomise01(Type& value)
 }
 
 
+template<class Type>
+Type Foam::cachedRandom::globalSample01()
+{
+    Type value = -GREAT*pTraits<Type>::one;
+
+    if (Pstream::master())
+    {
+        value = sample01<Type>();
+    }
+
+    reduce(value, maxOp<Type>());
+
+    return value;
+}
+
+
+template<class Type>
+Type Foam::cachedRandom::globalPosition(const Type& start, const Type& end)
+{
+    Type value = -GREAT*pTraits<Type>::one;
+
+    if (Pstream::master())
+    {
+        value = position<Type>(start, end);
+    }
+
+    reduce(value, maxOp<Type>());
+
+    return value;
+}
+
+
+template<class Type>
+void Foam::cachedRandom::globalRandomise01(Type& value)
+{
+    value = -GREAT*pTraits<Type>::one;
+
+    if (Pstream::master())
+    {
+        value = sample01<Type>();
+    }
+
+    reduce(value, maxOp<Type>());
+}
+
+
 // ************************************************************************* //