remove unused headers

makefile

 MPICXX  = mpicxx
 LINKER  = mpicxx
 DEFINES =
-CFLAGS  =
+CFLAGS  = -Wall \
+		  -O2
 
 LIBS = -lfftw3_mpi \
 	   -lfftw3 \
@@ -14,9 +15,9 @@ src := \
 	transp.cpp \
 	field_descriptor.cpp
 
-obj := $(patsubst %.cpp, ./obj/%.cpp.o, ${src})
+obj := $(patsubst %.cpp, ./obj/%.o, ${src})
 
-./obj/%.cpp.o: %.cpp
+./obj/%.o: %.cpp
 	${MPICXX} ${DEFINES} \
 		${CFLAGS} \
 		-c $^ -o $@
@@ -28,3 +29,6 @@ transpose_2D: ${obj}
 		${LIBS} \
 		${NULL}
 
+clean:
+	rm ./obj/*.o
+	rm t2D

src/field_descriptor.cpp

+#include <stdlib.h>
 #include "field_descriptor.hpp"
 
+extern int myrank, nprocs;
 
 field_descriptor::field_descriptor(
         int ndims,
@@ -162,3 +164,13 @@ field_descriptor* field_descriptor::get_transpose()
     return new field_descriptor(this->ndims, n, this->mpi_dtype);
 }
 
+
+int resize(
+        field_descriptor *fi,
+        fftwf_complex *ai,
+        field_descriptor *fo,
+        fftwf_complex *ao)
+{
+    return EXIT_SUCCESS;
+}
+

src/field_descriptor.hpp

-#include <stdio.h>
-#include <stdlib.h>
-#include <math.h>
 #include <mpi.h>
 #include <fftw3-mpi.h>
 
@@ -8,11 +5,11 @@
 
 #define __FIELD_DESCRIPTOR__
 
-extern int myrank, nprocs;
-
 class field_descriptor
 {
     public:
+
+        /* data */
         int *sizes;
         int *subsizes;
         int *starts;
@@ -20,22 +17,48 @@ class field_descriptor
         int local_size, full_size;
         MPI_Datatype mpi_array_dtype, mpi_dtype;
 
+
+        /* methods */
         field_descriptor(
                 int ndims,
                 int *n,
                 MPI_Datatype element_type);
         ~field_descriptor();
+
+        /* io is performed using MPI_File stuff, and our
+         * own mpi_array_dtype that was defined in the constructor.
+         * */
         int read(
                 const char *fname,
                 void *buffer);
         int write(
                 const char *fname,
                 void *buffer);
+
+        /* a function that generates the transposed descriptor.
+         * don't forget to delete the result once you're done with it.
+         * the transposed descriptor is useful for io operations.
+         * */
         field_descriptor *get_transpose();
+
+        /* we don't actually need the transposed descriptor to perform
+         * the transpose operation: we only need the in/out fields.
+         * */
         int transpose(
                 float *input,
                 float *output);
 };
 
+
+/* given two arrays of the same dimension, we do simple resizes in
+ * Fourier space: either chop off high modes, or pad with zeros.
+ * the arrays are assumed to use fftw layout.
+ * */
+int resize(
+        field_descriptor *fi,
+        fftwf_complex *ai,
+        field_descriptor *fo,
+        fftwf_complex *ao);
+
 #endif//__FIELD_DESCRIPTOR__
 

src/transp.cpp

+#include <stdio.h>
+#include <stdlib.h>
 #include "field_descriptor.hpp"
 
 int myrank, nprocs;