制作python和fortran的朋友

Question

假设我们需要在python程序中调用fortran函数,它返回一些值.我发现以这种方式重写fortran代码:

subroutine pow2(in_x, out_x)
      implicit none
      real, intent(in)      :: in_x
!f2py real, intent(in, out) :: out_x
      real, intent(out)     :: out_x
      out_x = in_x ** 2
      return
end

并以这种方式在python中调用它:

import modulename
a = 2.0
b = 0.0
b = modulename.pow2(a, b)

给我们工作的结果.我可以用其他方式调用fortran函数,因为我认为第一种方式有点笨拙吗？

Answer 1

我认为你只需稍微改变你的f2py函数签名(这out_x只是intent(out)而且in_x只是intent(in)):

subroutine pow2(in_x, out_x)
  implicit none
  real, intent(in)   :: in_x
  !f2py real, intent(in) :: in_x
  real, intent(out)     :: out_x
  !f2py real, intent(out) :: out_x
  out_x = in_x ** 2
  return
end subroutine pow2

现在编译:

f2py -m test -c test.f90

现在运行:

>>> import test
>>> test.pow2(3)   #only need to pass intent(in) parameters :-)
9.0
>>>

请注意,在这种情况下,f2py能够正确扫描函数的签名而无需特殊!f2py注释:

!test2.f90
subroutine pow2(in_x, out_x)
  implicit none
  real, intent(in)   :: in_x
  real, intent(out)     :: out_x
  out_x = in_x ** 2
  return
end subroutine pow2

编译:

f2py -m test2 -c test2.f90

跑:

>>> import test2
>>> test2.pow2(3)   #only need to pass intent(in) parameters :-)
9.0
>>>