Tuple Comparison Operations

The standard comparisons (<, <=, >, >=, ==, !=, in , not in ) work exactly the same among tuples as they do among strings. The tuples are compared element by element. If the corresponding elements are the same type, ordinary comparison rules are used. If the corresponding elements are different types, the type names are compared, since there is almost no other rational basis for comparison.

>>> 
a=(1,2,3,4,5)

>>> 
b=(9,8,7,6,5)

>>> 
if a < b: print "a smaller"

>>> 
else: print "b smaller"

a smaller
>>> 
print 3 in a

True
>>> 
print 3 in b

False
            

Here's a longer example.

Example 13.1. redblack.py

#!/usr/bin/env python
import random
n= random.randrange(38)
if n == 0:
    print '0', 'green'
elif n == 37:
    print  '00', 'green'
elif n in ( 1,3,5,7,9, 12,14,16,18, 19,21,23,25,27, 30,32,34,36 ):
    print n, 'red'
else:
    print n, 'black'

This script will create a random number, setting aside the zero and double zero. If the number is in the tuple of red spaces on the roulette layout, this is printed. If none of the other rules are true, the number is in one of the black spaces.

Clearly the heart of this script is the extended if-statement which contains the tuple of red positions on the roulette wheel. This should be rewritten as a function.