Python-尝试使用另一个模块中一个模块的名称值

Question

I'm a newbie at programming. Going to fire that one straight out there. Now I'm going to list three modules of code:

def GCD(x,y):
#gives the Greatest Common Divisor of two values.
while y != 0:
    r = x
    while r >= y: #these two lines are used to 
        r -= y    #calculate remainder of x/y
    x = y
    y = r
print x

This is the original program I wrote, based on Euclidean Algorithm for GCD. It functions correctly. I now want to remove the two commented lines above and replace it with a call to a further module I made, which calculates the remainder:

Remainder Calculator

def xy(x, y):
#Gives the remainder of the division of x by y. Outputs as r.
   while x >= y:
       x -= y
   r = x

This program also functions correctly. I want to use the value of the name 'r' in my edited program. I have attempted to do this below, but it causes problems:

def GCD(x,y):
import remainder
#gives the Greatest Common Divisor of two values.
while y != 0:
    remainder.xy(x,y)
    from remainder import r #here is the problem. This line is my attempt at 
                            #importing the value of r from the remainder calculating
                            #module into this module. This line is incorrect. 
    x = y
    y = r #Python cannot find 'r'. I want to use the value for 'r' from the execution
          #of the remainder calculating module. Attempts to find how have been
          #unsuccessful.
print x

I need to find out how to use the calculated value of 'r' from my xy module in my second GCD module. I have tried using

global r

in my module though I have had no success. I'm not sure if I am interpreting the function of 'global' correctly.

I would appreciate your help.

Jet Holt

Answer 1

If I understand you correctly:

from remainder import xy
def GCD(x,y): 
    #gives the Greatest Common Divisor of two values.
    while y != 0:
        r = xy(x,y)
        x = y
        y = r 
    print x

and

def xy(x, y):
#Gives the remainder of the division of x by y. Outputs as r.
   while x >= y:
       x -= y
   return x