fortran - How to declare the unknown number of line from file -

i have work file can change number of line due previous operation(from python script), , number of line used declare other variable, this.

integer numberofline  !this not work,of course. real(8) f(fixeddimension,numberofline) integer, parameter :: newdimension = anumber*numberofline 

how can declare numberofline properly. thanks. can pass number of line python, basicly know number after python operation complete

if declare parameter, value must fixed @ compile time. integer, parameter :: newdimension = anumber * numberofline cannot work if compiler doesn't know value of numberofline.

what can use allocatable arrays:

program test_alloc      implicit none     integer, parameter :: dp = selected_real_kind(p=15)     real(kind=dp), dimension(:,:), allocatable :: f     integer ::     integer, parameter :: fixeddimension = 10      print *, "enter i"     read(*, *)      allocate (a(fixeddimension, i))     =     print *,  end program test_alloc