add ability to use my FORTRAN implementation of the hypergeometric fu…

…nction

mod_f2py.F90

@@ -7,6 +7,7 @@ MODULE mod_f2py
     CONTAINS
 
     ! Include functions and subroutines ...
+    INCLUDE "mod_f2py/sub_hypergeometric.f90"
     INCLUDE "mod_f2py/sub_t_CDF.f90"
     INCLUDE "mod_f2py/sub_t_PDF.f90"
 END MODULE mod_f2py

mod_f2py/sub_hypergeometric.f90

@@ -0,0 +1,21 @@
+PURE SUBROUTINE sub_hypergeometric(a, b, c, z, ans)
+    !f2py threadsafe
+
+    ! Import standard modules ...
+    USE ISO_C_BINDING
+
+    ! Import my modules ...
+    USE mod_safe, ONLY: func_hypergeometric
+
+    IMPLICIT NONE
+
+    ! Declare inputs/outputs ...
+    REAL(kind = C_DOUBLE), INTENT(in)                                           :: a
+    REAL(kind = C_DOUBLE), INTENT(in)                                           :: b
+    REAL(kind = C_DOUBLE), INTENT(in)                                           :: c
+    REAL(kind = C_DOUBLE), INTENT(in)                                           :: z
+    REAL(kind = C_DOUBLE), INTENT(out)                                          :: ans
+
+    ! Calculate answer ...
+    ans = func_hypergeometric(a, b, c, z)
+END SUBROUTINE sub_hypergeometric

tests/func_t_CDF.py

@@ -15,7 +15,7 @@
 from mod_f2py import mod_f2py
 
 # Define function ...
-def t_CDF(x, dof):
+def t_CDF(x, dof, /, *, fortran = True):
     """This function calculates the CDF of Student's t-distribution in the same
     way as the FORTRAN function in this repository.
     """
@@ -52,7 +52,10 @@ def t_CDF(x, dof):
         z = - (x ** 2 / dof)
 
         # Calculate CDF ...
-        ans = a + x * math.gamma(b) * scipy.special.hyp2f1(a, b, c, z) / (math.sqrt(dof * math.pi) * math.gamma(0.5 * dof))
+        if fortran:
+            ans = a + x * math.gamma(b) * mod_f2py.sub_hypergeometric(a, b, c, z) / (math.sqrt(dof * math.pi) * math.gamma(0.5 * dof))
+        else:
+            ans = a + x * math.gamma(b) * scipy.special.hyp2f1(a, b, c, z) / (math.sqrt(dof * math.pi) * math.gamma(0.5 * dof))
 
     # Return answer ...
     return ans

tests/func_t_PDF.py

@@ -15,7 +15,7 @@
 from mod_f2py import mod_f2py
 
 # Define function ...
-def t_PDF(x, dof):
+def t_PDF(x, dof, /):
     """This function calculates the PDF of Student's t-distribution in the same
     way as the FORTRAN function in this repository.
     """