func1x func2xy GlobVar2100 is like this M1py func2xy It is as if func2 was

Func1x func2xy globvar2100 is like this m1py func2xy

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func1(x) func2(x,y) GlobVar2=[1,0,0] is like this… M1.py func2(x,y) It is as if func2 was defined in M1.py Using Stuff Within a Module M.py The functions and global variables in M.py can be used throughout M.py without the dot notation There are rules about when a module M2.py can be imported by a module M1.py
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2/18/2016 5 Does this Always Work? Yes, if M2.py is a module that is part of the CS 1110 Python installation, e.g., math numpy urllib2 string scipy PIL random timeit . import M2 : M1.py Does this Always Work? No UNLESS M1.py and M2.py are each in the “current working directory ”. . import M2 : M1.py Comments on “Launching” a Python Computation In what follows, this will be how we indicate what’s in the “current working directory” And this will mean we are in the command shell and in the “current working directory” cwd > import M2 M1.py cwd > python M1.py Result: the script in M1.py is executed. M2.py import M2 M1.py M2.py cwd > python M1.py Result: the script in M1.py is executed. The script in M2.py is not executed import M2 M1.py M2.py cwd > python M1.py Result: Nothing happens because there is no script in M1.py to execute.
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6 M2 M1 M1.py We now focus our attention on the mechanics behind function calls.Somewhat Like Plugging into a Formula For the simple kind of fruitful functions that we have been considering, there is a substitution process. Exactly how does it work?
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2/18/2016 7 We Use This Example… def T(s): “““ Returns as int the number of minutes from 12:00 to the time specified by s. PreC: s is a length-5 string of the form hh:mm ’ that specifies the time.””” h = int(s[:2]) m = int(s[3:]) if h<12: z = 60*h+m else: z = m return z A Script s1 = ‘11:15’ s2 = ‘12:05’ x = T(s1) y = T(s2) if y>=x: numMin = y-x else: numMin = (y+720)-x This assigns to numMin the number of minutes in a class that starts at the time specified by s1 and ends at the time specified by s2 . function call function call A Script s1 = ‘11:15’ s2 = ‘12:05’ x = T(s1) y = T(s2) if y>=x: numMin = y-x else: numMin = (y+720)-x print numMin Prints the number of minutes in a class that starts at the time specified by s1 and ends at the time specified by s2 . Let us step through its execution. s1 = ‘11:15’ s2 = ‘12:05’ x = T(s1) y = T(s2) if y>=x: numMin = y-x else: numMin = (y+720)-x print numMin 1 s1 s2 x y numMin This box is called Global Space. It includes all the variables associated with the script. The red dot indicates the next thing to do in the script. s1 = ‘11:15’ s2 = ‘12:05’ x = T(s1) y = T(s2) if y>=x: numMin = y-x else: numMin = (y+720)-x print numMin 2 s1 s2 x y numMin ‘11:15’ s1 = ‘11:15’ s2 = ‘12:05’
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  • Spring '08
  • DAVIDGRIES
  • Subroutine, Return statement, Control flow, nu mMi, M1.py

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