示例:
help([[1, 2, 2], [1, 1, 2]])
返回 2。
def help(num):
lst = ()
for n in num:
return(len(lst))
所以我需要桌上所有数字的总和
另一个例子:
help([[32, 12, 52, 63], [32, 64, 67, 52], [64, 64, 17, 34], [34, 17, 76, 32]])
返回: 9
示例:
help([[1, 2, 2], [1, 1, 2]])
返回 2。
def help(num):
lst = ()
for n in num:
return(len(lst))
所以我需要桌上所有数字的总和
另一个例子:
help([[32, 12, 52, 63], [32, 64, 67, 52], [64, 64, 17, 34], [34, 17, 76, 32]])
返回: 9
def allElementsInTable(table):
for row in table:
for elem in row:
yield elem
演示 :
>>> set(allElementsInTable([[1,2,2],[1,1,2]]))
{1,2}
>>> len(set(allElementsInTable([[1,2,2],[1,1,2]])))
2
如果您做了很多表格操作操作, 您可能想要查看 < code> numpy 数组 。
试试这个 (< a href=>"http://docs.python.org/library/itertools.html#itertools. lex" rel="nofollow">itertools. 链 用于“ contailate” the exterables):
table = [ [32, 12, 52, 63],
[32, 64, 67, 52],
[64, 64, 17, 34],
[34, 17, 76, 32] ]
from itertools import chain
n_unique_values = len(set( chain(*table) ))
print n_unique_values # prints 9
>>> x = [[1, 2, 2], [1, 1, 2]]
>>> unique_items = lambda n: len(set(n))
>>> map(unique_items, x)
[2, 2]
@garnertb当然是正确的,
>>> x = [[1, 2, 2], [1, 1, 2]]
>>> map(len, map(set, x))
[2, 2]
问题在于如果x变长,
>>> import itertools
>>> itertools.imap(len, itertools.imap(set, x))
<itertools.imap object at 0xb7437b8c>
compound_list = []
for sublist in lists:
compound_list += sublist
len(set(compound_list))
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