Remove PREC flag to set the computation precision.

The code by default works only with double precision arithmetics.  Quad
precision arithmetics can be added as an option in the future.

Signed-off-by: Grzegorz Kowal <grzegorz@amuncode.org>

src/integrals.F90

@@ -163,7 +163,7 @@ module integrals
 ! local variables
 !
     integer      :: iret
-    real(kind=PREC) :: dvol
+    real(kind=8) :: dvol
 
 ! local arrays
 !

src/make.default

@@ -22,12 +22,6 @@ SIGNALS      = N
 MPI          = N
 OMP          = N
 
-# precision flag:
-#
-#   PREC         - arithmetic precision: 4 for single, 8 for double precision
-#
-PREC         = 4
-
 # output data format
 #
 #   OUTPUT       - the format of output data; so far only HDF5

src/makefile

@@ -104,10 +104,6 @@ ifneq ($(COMPRESS),NONE)
 FFLAGS  += -DCOMPRESS -D${COMPRESS}
 endif
 
-# precision
-#
-FFLAGS  += -DPREC=${PREC}
-
 # time integration method
 #
 FFLAGS  += -D${TIME}