[Tutor] Modules and variable usage in functions from other files

[Richard Bekenstein]

   Dear All,

   I have a main .py script which contains code that occasionally calls some
   functions. This script calls in these defined functions from other .py
   files in the same directory as the main .py. However, even after importing
   the functions from the different .py files, I get error messages, such as
   "global name 'np' is not defined" even though I define "import numpy as
   np" initially in my main .py script.
   To show some detail, I import some modules at the beggining of my main .py
   script as such:

       from scipy.constants import m_p,G,k
       import numpy as np
       from math import cos, pi, floor
       import matplotlib.pyplot as plt
       from findall import findall
       from pylab import *
       import sys
       import timeit
       from copy import copy
       from array import array
       from bol_heatFTCS_nonadaptive import heatFTCS #this is my first
   user-defined function that calls the defined function 'heatFTCS' from file
   'bol_heatFTCS_nonadaptive.py'
       from bol_runge_kutta_functions import dy1_dt,dy2_dt,dy3_dt,dy5_dt
   #this is my second user-defined function that calls the defined functions
   'dyi_dt's from file 'bol_runge_kutta_functions.py'
       from bol_runge_kutta_evl_nonadaptive import runge_kutta_evl #this is
   my first user-defined function that calls the defined function
   'runge_kutta_evl' from file 'bol_runge_kutta_evl_nonadaptive.py'
       m_range,p_range,T_range,r_range,rho_range = np.loadtxt('(there are
   some other directories here that don't matter for this
   discussion)/planetary_structure_params.txt', unpack=True,
   usecols=[0,1,2,3,4])  #imports some data to 5 arrays


   When I run this main.py, I get an error message from the imported
   'runge_kutta_evl' function that numpy is not defined. Why is it that even
   though I have it defined in my script it does not recognize it in my
   function called to the script? It turns out that even if I then state
   'import numpy as np' in my 'runge_kutta_evl' function, I then another
   error that 'r_range' is not defined. But aren't 'r_range' and 'np'
   supposed to be accesible to all called functions in the main .py?

   Thank you,
   R.B.