''' Purpose: naming allows abstraction
    Author:  Jim Cohoon
    ID:      jpc
'''
# this is telling python that you want to be able to do some stuff
import math # this is asking python to use its math library in order to do fancy math things

# In every program you want to use math, you have to import math.
# You only have to put the import math statement once in the program.

# Standard libs are included with python
# You can include other .py files using import (This will come later)

print()

print( 'Python approximation of π:', math.pi )
print( 'Python approximation of Euler\'s number:', math.e )

print()
print()

a = math.radians( 30 )
b = math.radians( 45 )

print( 'sin( 30 ):', math.sin( a ) )
print( 'tan( 45 ):', math.tan( b ) )

print()

#remember_pi = math.pi

math.pi = 3 # uh oh.....

print ( math.pi ) # this is not good
#print( remember_pi )

# DON'T DO THIS. IT WILL MAKE YOU CRY!
# Every math.pi after line 33 is changed; the others are still safe but AGAIN DONT DO IT!