add cpnfigurable BUILDDIR in Makefiles

src/Makefile

 SUBDIRS := cluster sphere trapping
 SRCDIR=$(PWD)
 OBJDIR=$(SRCDIR)/objects
-BUILDDIR=$(SRCDIR)/../build
+ifndef BUILDDIR
+override BUILDDIR=$(SRCDIR)/../build
+endif
 DOCSDIR=$(SRCDIR)/../doc
 
-all: $(SUBDIRS)
+all: $(SUBDIRS) $(BUILDDIR)
 
 docs:
 	cd $(DOCSDIR)/src; doxygen config.dox
 
-$(SUBDIRS):
+$(BUILDDIR):
+	mkdir -p $(BUILDDIR)
+
+$(SUBDIRS): $(BUILDDIR)
 	$(MAKE) -C $@
 
-clean:
-	rm -f $(OBJDIR)/*.o
+clean: $(BUILDDIR)
+	$(MAKE) -C cluster clean
+	$(MAKE) -C sphere clean
+	$(MAKE) -C trapping clean
 
-wipe:
-	rm -f $(BUILDDIR)/cluster/*
-	rm -f $(BUILDDIR)/sphere/*
-	rm -f $(BUILDDIR)/trapping/*
-	rm -f $(OBJDIR)/*.o
+wipe: $(BUILDDIR)
+	$(MAKE) -C cluster wipe
+	$(MAKE) -C sphere wipe
+	$(MAKE) -C trapping wipe
 	if [ -d $(DOCSDIR)/build/html ]; then rm -r $(DOCSDIR)/build/html; fi
 	if [ -d $(DOCSDIR)/build/latex ]; then rm -r $(DOCSDIR)/build/latex; fi
 

src/cluster/Makefile

 ifndef BUILDDIR
-override BUILDDIR=../../build/cluster
+override BUILDDIR=../../build
+endif
+ifndef BUILDDIR_CLU
+override BUILDDIR_CLU=$(BUILDDIR)/cluster
 endif
 ifndef OBJDIR
 override OBJDIR=../objects
@@ -13,20 +16,23 @@ F_CLU_OBJS=$(OBJDIR)/clu.o $(OBJDIR)/edfb_clu.o
 CXX_CLU_OBJS=$(OBJDIR)/np_cluster.o $(OBJDIR)/Commons.o $(OBJDIR)/Configuration.o $(OBJDIR)/file_io.o $(OBJDIR)/Parsers.o $(OBJDIR)/sph_subs.o $(OBJDIR)/clu_subs.o $(OBJDIR)/cluster.o
 
 
-all: $(BUILDDIR)/clu $(BUILDDIR)/edfb_clu $(BUILDDIR)/np_cluster
+all: $(BUILDDIR_CLU)/clu $(BUILDDIR_CLU)/edfb_clu $(BUILDDIR_CLU)/np_cluster
+
+$(BUILDDIR_CLU):
+	mkdir -p $(BUILDDIR_CLU)
 
-$(BUILDDIR)/clu: $(OBJDIR)/clu.o
-	$(FC) $(FCFLAGS) -o $(BUILDDIR)/clu $(OBJDIR)/clu.o $(LDFLAGS)
+$(BUILDDIR_CLU)/clu: $(OBJDIR)/clu.o $(BUILDDIR_CLU)
+	$(FC) $(FCFLAGS) -o $(BUILDDIR_CLU)/clu $(OBJDIR)/clu.o $(LDFLAGS)
 
-$(BUILDDIR)/edfb_clu: $(OBJDIR)/edfb_clu.o
-	$(FC) $(FCFLAGS) -o $(BUILDDIR)/edfb_clu $(OBJDIR)/edfb_clu.o $(LDFLAGS)
+$(BUILDDIR_CLU)/edfb_clu: $(OBJDIR)/edfb_clu.o $(BUILDDIR_CLU)
+	$(FC) $(FCFLAGS) -o $(BUILDDIR_CLU)/edfb_clu $(OBJDIR)/edfb_clu.o $(LDFLAGS)
 
-$(BUILDDIR)/np_cluster: $(CXX_CLU_OBJS)
-	$(CXX) $(CXXFLAGS) -o $(BUILDDIR)/np_cluster $(CXX_CLU_OBJS) $(CXXLDFLAGS) 
+$(BUILDDIR_CLU)/np_cluster: $(CXX_CLU_OBJS) $(BUILDDIR_CLU)
+	$(CXX) $(CXXFLAGS) -o $(BUILDDIR_CLU)/np_cluster $(CXX_CLU_OBJS) $(CXXLDFLAGS) 
 
 clean:
 	rm -f $(F_CLU_OBJS) $(CXX_CLU_OBJS)
 
 wipe:
-	rm -f $(BUILDDIR)/clu $(BUILDDIR)/edfb_clu $(F_CLU_OBJS) $(CXX_CLU_OBJS)
+	rm -f $(BUILDDIR_CLU)/clu $(BUILDDIR_CLU)/edfb_clu $(BUILDDIR_CLU)/np_cluster $(F_CLU_OBJS) $(CXX_CLU_OBJS)
 

src/sphere/Makefile

 ifndef BUILDDIR
-override BUILDDIR=../../build/sphere
+override BUILDDIR=../../build
+endif
+ifndef BUILDDIR_SPH
+override BUILDDIR_SPH=$(BUILDDIR)/sphere
 endif
 ifndef OBJDIR
 override OBJDIR=../objects
@@ -13,20 +16,23 @@ F_SPH_OBJS=$(OBJDIR)/edfb_sph.o $(OBJDIR)/sph.o
 CXX_SPH_OBJS=$(OBJDIR)/np_sphere.o $(OBJDIR)/Commons.o $(OBJDIR)/Configuration.o $(OBJDIR)/file_io.o $(OBJDIR)/Parsers.o $(OBJDIR)/sph_subs.o $(OBJDIR)/sphere.o
 
 
-all: $(BUILDDIR)/edfb_sph $(BUILDDIR)/sph $(BUILDDIR)/np_sphere
+all: $(BUILDDIR_SPH)/edfb_sph $(BUILDDIR_SPH)/sph $(BUILDDIR_SPH)/np_sphere
+
+$(BUILDDIR_SPH):
+	mkdir -p $(BUILDDIR_SPH)
 
-$(BUILDDIR)/edfb_sph: $(OBJDIR)/edfb_sph.o
-	$(FC) $(FCFLAGS) -o $(BUILDDIR)/edfb_sph $(OBJDIR)/edfb_sph.o $(LDFLAGS)
+$(BUILDDIR_SPH)/edfb_sph: $(OBJDIR)/edfb_sph.o $(BUILDDIR_SPH)
+	$(FC) $(FCFLAGS) -o $(BUILDDIR_SPH)/edfb_sph $(OBJDIR)/edfb_sph.o $(LDFLAGS)
 
-$(BUILDDIR)/sph: $(OBJDIR)/sph.o
-	$(FC) $(FCFLAGS) -o $(BUILDDIR)/sph $(OBJDIR)/sph.o $(LDFLAGS)
+$(BUILDDIR_SPH)/sph: $(OBJDIR)/sph.o $(BUILDDIR_SPH)
+	$(FC) $(FCFLAGS) -o $(BUILDDIR_SPH)/sph $(OBJDIR)/sph.o $(LDFLAGS)
 
-$(BUILDDIR)/np_sphere: $(CXX_SPH_OBJS)
-	$(CXX) $(CXXFLAGS) -o $(BUILDDIR)/np_sphere $(CXX_SPH_OBJS) $(CXXLDFLAGS) 
+$(BUILDDIR_SPH)/np_sphere: $(CXX_SPH_OBJS) $(BUILDDIR_SPH)
+	$(CXX) $(CXXFLAGS) -o $(BUILDDIR_SPH)/np_sphere $(CXX_SPH_OBJS) $(CXXLDFLAGS) 
 
 clean:
 	rm -f $(F_SPH_OBJS) $(CXX_SPH_OBJS)
 
 wipe:
-	rm -f $(BUILDDIR)/edfb_sph $(BUILDDIR)/sph $(F_SPH_OBJS) $(CXX_SPH_OBJS)
+	rm -f $(BUILDDIR_SPH)/edfb_sph $(BUILDDIR_SPH)/sph $(BUILDDIR_SPH)/np_sphere $(F_SPH_OBJS) $(CXX_SPH_OBJS)
 

src/trapping/Makefile

 ifndef BUILDDIR
-override BUILDDIR=../../build/trapping
+override BUILDDIR=../../build
+endif
+ifndef BUILDDIR_TRA
+override BUILDDIR_TRA=$(BUILDDIR)/trapping
 endif
 ifndef OBJDIR
 override OBJDIR=../objects
@@ -12,20 +15,23 @@ F_TRAP_OBJS=$(OBJDIR)/frfme.o $(OBJDIR)/lffft.o
 
 CXX_TRAP_OBJS=$(OBJDIR)/np_trapping.o $(OBJDIR)/cfrfme.o $(OBJDIR)/clffft.o $(OBJDIR)/Parsers.o $(OBJDIR)/Commons.o $(OBJDIR)/Configuration.o $(OBJDIR)/file_io.o $(OBJDIR)/sph_subs.o $(OBJDIR)/tra_subs.o
 
-all: $(BUILDDIR)/frfme $(BUILDDIR)/lffft $(BUILDDIR)/np_trapping
+all: $(BUILDDIR_TRA)/frfme $(BUILDDIR_TRA)/lffft $(BUILDDIR_TRA)/np_trapping
+
+$(BUILDDIR_TRA):
+	mkdir -p $(BUILDDIR_TRA)
 
-$(BUILDDIR)/frfme: $(OBJDIR)/frfme.o
-	$(FC) $(FCFLAGS) -o $(BUILDDIR)/frfme $(OBJDIR)/frfme.o $(LDFLAGS)
+$(BUILDDIR_TRA)/frfme: $(OBJDIR)/frfme.o $(BUILDDIR_TRA)
+	$(FC) $(FCFLAGS) -o $(BUILDDIR_TRA)/frfme $(OBJDIR)/frfme.o $(LDFLAGS)
 
-$(BUILDDIR)/lffft: $(OBJDIR)/lffft.o
-	$(FC) $(FCFLAGS) -o $(BUILDDIR)/lffft $(OBJDIR)/lffft.o $(LDFLAGS)
+$(BUILDDIR_TRA)/lffft: $(OBJDIR)/lffft.o $(BUILDDIR_TRA)
+	$(FC) $(FCFLAGS) -o $(BUILDDIR_TRA)/lffft $(OBJDIR)/lffft.o $(LDFLAGS)
 
-$(BUILDDIR)/np_trapping: $(CXX_TRAP_OBJS)
-	$(CXX) $(CXXFLAGS) -o $(BUILDDIR)/np_trapping $(CXX_TRAP_OBJS) $(CXXLDFLAGS) 
+$(BUILDDIR_TRA)/np_trapping: $(CXX_TRAP_OBJS) $(BUILDDIR_TRA)
+	$(CXX) $(CXXFLAGS) -o $(BUILDDIR_TRA)/np_trapping $(CXX_TRAP_OBJS) $(CXXLDFLAGS) 
 
 clean:
 	rm -f $(F_TRAP_OBJS) $(CXX_TRAP_OBJS)
 
 wipe:
-	rm -f $(BUILDDIR)/frfme $(BUILDDIR)/lffft $(F_TRAP_OBJS) $(CXX_TRAP_OBJS)
+	rm -f $(BUILDDIR_TRA)/frfme $(BUILDDIR_TRA)/lffft $(BUILDDIR_TRA)/np_trapping $(F_TRAP_OBJS) $(CXX_TRAP_OBJS)