From 27f5b84c07f4b156bc1562468f321f42b7773081 Mon Sep 17 00:00:00 2001
From: Daniel Schwen <daniel.schwen@inl.gov>
Date: Fri, 24 Jan 2020 10:57:24 -0700
Subject: [PATCH] Higher order type transforms (#401)

---
 src/executioners/SpectralExecutionerBase.C | 14 +++++++--
 src/userobjects/FFTWBufferBase.C           | 35 ++++++++++++++++++----
 2 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/src/executioners/SpectralExecutionerBase.C b/src/executioners/SpectralExecutionerBase.C
index 0f39cbfd..13ad4c78 100644
--- a/src/executioners/SpectralExecutionerBase.C
+++ b/src/executioners/SpectralExecutionerBase.C
@@ -56,13 +56,23 @@ SpectralExecutionerBase::execute()
   _fe_problem.outputStep(EXEC_INITIAL);
   _fe_problem.advanceState();
 
-  mooseInfo("SpectralExecutionerBase::execute()");
-
   auto & c = getFFTBuffer<Real>("c");
   c.forward();
 
+  auto & R = getFFTBuffer<RealVectorValue>("R");
+  R.forward();
+
   _time_step = 1;
   _fe_problem.execute(EXEC_FINAL);
   _time = _time_step;
   _fe_problem.outputStep(EXEC_FINAL);
+  _fe_problem.advanceState();
+
+  c.backward();
+  R.backward();
+
+  _time_step = 2;
+  _fe_problem.execute(EXEC_FINAL);
+  _time = _time_step;
+  _fe_problem.outputStep(EXEC_FINAL);
 }
diff --git a/src/userobjects/FFTWBufferBase.C b/src/userobjects/FFTWBufferBase.C
index fdeafc52..420e419e 100644
--- a/src/userobjects/FFTWBufferBase.C
+++ b/src/userobjects/FFTWBufferBase.C
@@ -21,11 +21,38 @@ FFTWBufferBase<T>::FFTWBufferBase(const InputParameters & parameters)
     _perf_fft(this->registerTimedSection("fftw_execute", 2))
 {
   // create plans
-  std::vector<fftw_r2r_kind> kind(_dim, FFTW_R2HC);
   {
     TIME_SECTION(_perf_plan);
-    _forward_plan = fftw_plan_r2r(_dim, _grid.data(), _start, _start, kind.data(), FFTW_ESTIMATE);
-    _backward_plan = fftw_plan_r2r(_dim, _grid.data(), _start, _start, kind.data(), FFTW_ESTIMATE);
+
+    std::vector<fftw_r2r_kind> forward_kind(_dim, FFTW_R2HC);
+    _forward_plan = fftw_plan_many_r2r(_dim,
+                                       _grid.data(),
+                                       _how_many,
+                                       _start,
+                                       _grid.data(),
+                                       _stride,
+                                       1,
+                                       _start,
+                                       _grid.data(),
+                                       _stride,
+                                       1,
+                                       forward_kind.data(),
+                                       FFTW_ESTIMATE);
+
+    std::vector<fftw_r2r_kind> backward_kind(_dim, FFTW_HC2R);
+    _backward_plan = fftw_plan_many_r2r(_dim,
+                                        _grid.data(),
+                                        _how_many,
+                                        _start,
+                                        _grid.data(),
+                                        _stride,
+                                        1,
+                                        _start,
+                                        _grid.data(),
+                                        _stride,
+                                        1,
+                                        backward_kind.data(),
+                                        FFTW_ESTIMATE);
   }
 }
 
@@ -41,8 +68,6 @@ template <typename T>
 void
 FFTWBufferBase<T>::forward()
 {
-  mooseInfo("FFTWBufferBase<T>::forward()");
-
   // execute plan
   {
     TIME_SECTION(_perf_fft);