Resolve "allow 64-bit indexing in heffte interface"

Closes #91 (closed)

src/FFT/FFT.hpp

@@ -57,8 +57,8 @@ namespace ippl {
          * 1D FFTs we just have to make the length in other
          * dimensions to be 1.
          */
-        std::array<long long, 3> low;
-        std::array<long long, 3> high;
+        std::array<long long, Dim> low;
+        std::array<long long, Dim> high;
 
         const NDIndex<Dim>& lDom = layout.getLocalNDIndex();
 
@@ -97,7 +97,7 @@ namespace ippl {
          heffteOptions.use_pencils = params.getPencils();
          heffteOptions.use_reorder = params.getReorder();
 
-         heffte_m = std::make_shared<heffte::fft3d<heffteBackend>>
+         heffte_m = std::make_shared<heffte::fft3d<heffteBackend, long long>>
                     (inbox, outbox, Ippl::getComm(), heffteOptions);
 
     }
@@ -213,10 +213,10 @@ namespace ippl {
          * 1D FFTs we just have to make the length in other
          * dimensions to be 1.
          */
-        std::array<long long, 3> lowInput;
-        std::array<long long, 3> highInput;
-        std::array<long long, 3> lowOutput;
-        std::array<long long, 3> highOutput;
+        std::array<long long, Dim> lowInput;
+        std::array<long long, Dim> highInput;
+        std::array<long long, Dim> lowOutput;
+        std::array<long long, Dim> highOutput;
 
         const NDIndex<Dim>& lDomInput = layoutInput.getLocalNDIndex();
         const NDIndex<Dim>& lDomOutput = layoutOutput.getLocalNDIndex();
@@ -266,7 +266,7 @@ namespace ippl {
          heffteOptions.use_pencils = params.getPencils();
          heffteOptions.use_reorder = params.getReorder();
 
-         heffte_m = std::make_shared<heffte::fft3d_r2c<heffteBackend>>
+         heffte_m = std::make_shared<heffte::fft3d_r2c<heffteBackend, long long>>
                     (inbox, outbox, params.getRCDirection(), Ippl::getComm(),
                      heffteOptions);