python集合用法实例分析

本文实例讲述了python集合用法。分享给大家供大家参考。具体分析如下：

    # sets are unordered collections of unique hashable elements
    # Python23 tested   vegaseat   09mar2005
    # Python v2.4 has sets built in
    import sets
    print "List the functions within module 'sets':"
    for funk in dir(sets):
      print funk
    # create an empty set
    set1 = set([])
    # now load the set
    for k in range(10):
      set1.add(k)
    print "\nLoaded a set with 0 to 9:"
    print set1
    set1.add(7)
    print "Tried to add another 7, but it was already there:"
    print set1
    # make a list of fruits as you put them into a basket
    basket = ['apple', 'orange', 'apple', 'pear', 'orange', 'banana']
    print "\nThe original list of fruits:"
    print basket
    # create a set from the list, removes the duplicates
    fruits = sets.Set(basket)
    print "\nThe set is unique, but the order has changed:"
    print fruits
    # let's get rid of some duplicate words
    str1 = "Senator Strom Thurmond dressed as as Tarzan"
    print "\nOriginal string:"
    print str1
    print "A list of the words in the string:"
    wrdList1 = str1.split()
    print wrdList1
    # now create a set of unique words
    strSet = sets.Set(wrdList1)
    print "The set of the words in the string:"
    print strSet
    print "Convert set back to string (order has changed!):"
    print " ".join(strSet)
    print
    # comparing two sets, bear with me ...
    colorSet1 = sets.Set(['red','green','blue','black','orange','white'])
    colorSet2 = sets.Set(['black','maroon','grey','blue'])
    print "colorSet1 =", colorSet1
    print "colorSet2 =", colorSet2
    # same as (colorSet1 - colorSet2)
    colorSet3 = colorSet1.difference(colorSet2)
    print "\nThese are the colors in colorSet1 that are not in colorSet2:"
    print colorSet3
    # same as (colorSet1 | colorSet2)
    colorSet4 = colorSet1.union(colorSet2)
    print "\nThese are the colors appearing in both sets:"
    print colorSet4
    # same as (colorSet1 ^ colorSet2)
    colorSet5 = colorSet1.symmetric_difference(colorSet2)
    print "\nThese are the colors in colorSet1 or in colorSet2, but not both:"
    print colorSet5
    # same as (colorSet1 & colorSet2)
    colorSet6 = colorSet1.intersection(colorSet2)
    print "\nThese are the colors common to colorSet1 and colorSet2:"
    print colorSet6

希望本文所述对大家的Python程序设计有所帮助。