ENH: support frequency or period for Sine/Square Function1 (#1917)

- For slow oscillations it can be more intuitive to specify the
  period.

ENH: separate mark/space for Square

- makes it easier to tailor the desired intervals.

BUG: incorrect square wave fraction with negative phase shifts

ENH: additional cosine Function1

STYLE: avoid code duplication by inheriting Cosine/Square from Sine.

applications/test/Function1/case1/constant/function1Properties

@@ -61,4 +61,48 @@ rampf1
 }
 
 
+sine1
+{
+    type        sine;
+    frequency   0.1;
+    scale       1;
+    level       0;
+}
+
+sine2
+{
+    type        sine;
+    period      10;
+    scale       1;
+    level       0;
+}
+
+cosine1
+{
+    type        cosine;
+    period      10;
+    scale       1;
+    level       0;
+}
+
+
+sine6
+{
+    type        sine;
+    period      6;
+    t0          -1.5;  // want cos
+    scale       1;
+    level       0;
+}
+
+
+cosine6
+{
+    type        cosine;
+    period      6;
+    scale       1;
+    level       0;
+}
+
+
 // ************************************************************************* //

applications/test/plotFunction1/Make/files

@@ -0,0 +1,3 @@
+Test-plotFunction1.C
+
+EXE = $(FOAM_USER_APPBIN)/Test-plotFunction1

applications/test/plotFunction1/Make/options

@@ -0,0 +1,15 @@
+EXE_INC = \
+    -DFULLDEBUG -g -O0 \
+    -I$(LIB_SRC)/lagrangian/intermediate/lnInclude \
+    -I$(LIB_SRC)/thermophysicalModels/radiation/lnInclude \
+    -I$(LIB_SRC)/thermophysicalModels/thermophysicalFunctions/lnInclude \
+    -I$(LIB_SRC)/finiteVolume/lnInclude \
+    -I$(LIB_SRC)/meshTools/lnInclude
+
+EXE_LIBS = \
+    -llagrangianIntermediate \
+    -lradiationModels \
+    -lregionModels \
+    -lfiniteVolume \
+    -lmeshTools \
+    -lsampling

applications/test/plotFunction1/Test-plotFunction1.C

@@ -0,0 +1,105 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2020 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/>.
+
+Application
+    Test-plotFunction1
+
+Description
+    Plot scalar Function1 entries
+
+\*---------------------------------------------------------------------------*/
+
+#include "argList.H"
+#include "fieldTypes.H"
+#include "Function1.H"
+#include "PtrList.H"
+#include "Fstream.H"
+
+using namespace Foam;
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+int main(int argc, char *argv[])
+{
+    argList::noBanner();
+    argList::noParallel();
+    argList::setAdvanced("case");  // Hide -case : has no meaning here
+
+    argList::addOption("begin", "scalar", "The start time (default: 0)");
+    argList::addOption("end", "scalar", "The end time (default: 1)");
+    argList::addOption("incr", "scalar", "The time increment (default: 0.1)");
+    argList::addOption("timeBase", "scalar", "The time base (default: 1)");
+    argList::addNote
+    (
+        "Read scalar functions from each file and produces"
+        " time/value output for each"
+    );
+
+    argList::noMandatoryArgs();
+    argList::addArgument("file1");
+    argList::addArgument("...");
+    argList::addArgument("fileN");
+
+    #include "setRootCase.H"
+
+    const scalar begTime = args.getOrDefault<scalar>("begin", 0);
+    const scalar endTime = args.getOrDefault<scalar>("end", 1);
+    const scalar incrTime = args.getOrDefault<scalar>("incr", 0.1);
+    const scalar timeBase = args.getOrDefault<scalar>("timeBase", 1);
+
+    Info().precision(10);
+
+    for (label argi=1; argi < args.size(); ++argi)
+    {
+        IFstream is(args[argi]);
+
+        dictionary dict(is);
+
+        for (const entry& dEntry : dict)
+        {
+            autoPtr<Function1<scalar>> funPtr =
+                Function1<scalar>::New(dEntry.keyword(), dict);
+
+            auto& fun = *funPtr;
+
+            InfoErr<< nl;
+            fun.writeData(InfoErr);
+            InfoErr<< nl;
+
+            Info<< nl << "# " << fun.type() << nl;
+
+            for (scalar t = begTime; t < endTime; t += incrTime)
+            {
+                Info<< t << tab << fun.value(t*timeBase) << nl;
+            }
+            Info<< nl;
+        }
+    }
+
+    return 0;
+}
+
+
+// ************************************************************************* //