Simple examples to understand Sets in Python

Simple examples to understand Sets in Python.py

#!/usr/bin/env python

"""
Set - an unordered collection of unique and immutable objects
"""


def main():
    x = set('abcdef')
    y = set('bdexyz')

    print "X = ", x
    print "Y = ", y, '\n'

    print "Difference = ", x - y
    print "Union = ", x | y
    print "Intersection = ", x & y
    print "Symmetric Difference (XOR) = ", x ^ y
    print "Superset = ", x > y
    print "subset = ", x < y, '\n'

    for item in set('abc'):
        print item * 3

    print "'e' in x = ", 'e' in x, '\n'

    z = x.intersection(y)
    print z
    z.add('SPAM')   # insert one item
    print z
    z.update(set(['X', 'Y']))   # inserts multiple items
    print z
    z.remove('b')
    print z, '\n'

    S = {i for i in range(1, 4)}
    print S
    print "Type = ", type(S)
    print "Union = ", S | set([3, 4])
    print "Union = ", S.union([3, 4])
    print "Intersection = ", S.intersection((1, 3, 5))
    print "Subset = ", S.issubset(range(-5, 5)), '\n'

    print "Union = ", {1, 2, 3} | {4, 5}
    print "Union = ", {1, 2, 3}.union([3, 4])
    print "Intersection = ", {1, 2, 3}.intersection((1, 3, 5))
    print "Subset = ", {1, 2, 3}.issubset(range(-5, 5)), '\n'

    S = 'spammapaas'    # Strings
    S = set(S)
    print S
    S.add('alot')
    print S
    S.add((1, 2, 3))  # No list or dict but tuple is ok
    print S, '\n'

    # Sets are used to remove the duplicates
    L = [1, 1, 2, 5, 4, 3, 7, 8, 2, 5, 9, 8, 0]
    print "L = ", L
    print "set(L) = ", set(L)
    L = list(set(L))
    print "L = ", L, '\n'

    print set(dir(bytes)) - set(dir(bytearray))
    print set(dir(bytearray)) - set(dir(bytes))


if __name__ == '__main__':
    main()