add main routine

1 files changed, 73 insertions, 0 deletions

diff --git a/src/main.f90 b/src/main.f90
new file mode 100644
index 0000000..8c7467a
--- /dev/null
+++ b/src/main.f90
@@ -0,0 +1,73 @@
+PROGRAM integrator
+  USE quadratures
+  USE functions
+  IMPLICIT none
+
+  real(kind=8) :: ibeg, iend, val
+  integer(kind=4) :: poly_order
+  procedure(integrate), pointer :: numerical_int
+  procedure(funint), pointer :: fun
+  procedure(analytical_integral), pointer :: analytical_int
+  character(100) :: arg
+
+  IF (command_argument_count() < 4) STOP "4 arguments required"
+
+  call get_command_argument(2, arg)
+
+  IF      (arg == "exp")  THEN
+     fun            => my_exp
+     analytical_int => my_exp_int
+  ELSE IF (arg == "sin")  THEN
+     fun            => my_sin
+     analytical_int => my_sin_int
+  ELSE IF (arg == "poly") THEN
+     fun            => my_poly
+     analytical_int => my_poly_int
+  ELSE
+     STOP "bad second argument (should be 'exp', 'sin' or 'poly')"
+  END IF
+
+  
+  call get_command_argument(3, arg)
+
+  read (arg,*) ibeg
+  
+  call get_command_argument(4, arg)
+
+  read (arg,*) iend
+
+  
+  call get_command_argument(1, arg)
+
+  IF      (arg == "gauss")        THEN
+     numerical_int => gauss
+  ELSE IF (arg == "newton-cotes") THEN
+     numerical_int => newton_cotes
+  ELSE IF (arg == "analytical")   THEN
+     IF (this_image() == 1) write (*,*) analytical_int(ibeg, iend)
+     STOP
+  ELSE
+     STOP "bad first argument (should be 'gauss', 'newton-cotes'" &
+          // " or 'analytical')"
+  END IF
+
+  
+  IF (command_argument_count() < 5)                               &
+       STOP "5th argument (polynomial order) required"            &
+       // " for numerical integration"
+  
+  call get_command_argument(5, arg)
+  read (arg,*) poly_order
+
+  
+  IF (command_argument_count() > 5) THEN
+     call get_command_argument(6, arg)
+     read (arg,*) subintervals
+     IF (subintervals < 1) STOP "subintervals number must be positive"
+  END IF
+
+  val = numerical_int(ibeg, iend, fun, poly_order)
+
+  IF (this_image() == 1) write (*,*) val
+  
+END PROGRAM integrator