using variables of main file in imported file

Question

I am using python and cannot solve the problem myself. I defined the variables(rb. data) in the 'main file' below. And I imported 'hp file' to use hotplate function. ( i611Robot, Teachdata, MotionParam,Position are included in 'A file' )

from hp import *
from A import *

def main():
    rb = i611Robot()
    data = Teachdata()
    m1 = MotionParam(30,20,10,2,2)
    position_1 = Position(100,200,100,0,0,0)
    ...
    ....
    hotplate(rb)

if __name__ == '__main__':
    main()

And this is the 'hp file' which is imported.

from A import *
def hotplate(rb) :
    rb.motionparam( m1 )
    rb.move( position_1 ) 
    .......

But the problem is when I play 'main file', it says

File "main.py" line.., in <module>
    main()
File "main/py", line ...., in main
    hotplate()
File ".../hotplate.py", in line .., in hotplate
    rb.motionparam( m1 ) 
NameError : global name 'm1' is not defined

I already asked question about how to use rb in hotplate.py and get answer that I have to put rb in hotplate(). This works well. But another problem is that there are so many variables, parameters like rb and m1, position_1 that will be used in hotplate.py file. How can I use those all variables,instances,parameters in hotplate.py file.

Answer 1

As @Barmar already commented, functions should get their information from parameters.

Your code

What you're doing doesn't work:

def a():
    myVar = "Hello"
    b()


def b():
    print(myVar)


if __name__ == "__main__":
    a()

The function b doesn't know the variable myVar, the variable is out of scope.

Solution

What you have to do is to pass the arguments which the function needs to the function's parameters:

def a():
    myVar = "Hello"
    b(myVar)


def b(myArg):
    print(myArg)


if __name__ == "__main__":
    a()

Output

Hello

Learn about python functions here: https://www.w3schools.com/python/python_functions.asp