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| -rw-r--r-- | Doc/howto/functional.rst | 46 |
1 files changed, 23 insertions, 23 deletions
diff --git a/Doc/howto/functional.rst b/Doc/howto/functional.rst index 47a5bb9..2efe453 100644 --- a/Doc/howto/functional.rst +++ b/Doc/howto/functional.rst @@ -198,7 +198,7 @@ for it. You can experiment with the iteration interface manually: - >>> L = [1,2,3] + >>> L = [1, 2, 3] >>> it = iter(L) >>> it #doctest: +ELLIPSIS <...iterator object at ...> @@ -229,7 +229,7 @@ iterator. These two statements are equivalent:: Iterators can be materialized as lists or tuples by using the :func:`list` or :func:`tuple` constructor functions: - >>> L = [1,2,3] + >>> L = [1, 2, 3] >>> iterator = iter(L) >>> t = tuple(iterator) >>> t @@ -238,10 +238,10 @@ Iterators can be materialized as lists or tuples by using the :func:`list` or Sequence unpacking also supports iterators: if you know an iterator will return N elements, you can unpack them into an N-tuple: - >>> L = [1,2,3] + >>> L = [1, 2, 3] >>> iterator = iter(L) - >>> a,b,c = iterator - >>> a,b,c + >>> a, b, c = iterator + >>> a, b, c (1, 2, 3) Built-in functions such as :func:`max` and :func:`min` can take a single @@ -411,7 +411,7 @@ lengths of all the sequences. If you have two lists of length 3, the output list is 9 elements long: >>> seq1 = 'abc' - >>> seq2 = (1,2,3) + >>> seq2 = (1, 2, 3) >>> [(x, y) for x in seq1 for y in seq2] #doctest: +NORMALIZE_WHITESPACE [('a', 1), ('a', 2), ('a', 3), ('b', 1), ('b', 2), ('b', 3), @@ -479,7 +479,7 @@ Here's a sample usage of the ``generate_ints()`` generator: File "stdin", line 2, in generate_ints StopIteration -You could equally write ``for i in generate_ints(5)``, or ``a,b,c = +You could equally write ``for i in generate_ints(5)``, or ``a, b, c = generate_ints(3)``. Inside a generator function, ``return value`` causes ``StopIteration(value)`` @@ -695,17 +695,17 @@ truth values of an iterable's contents. :func:`any` returns ``True`` if any ele in the iterable is a true value, and :func:`all` returns ``True`` if all of the elements are true values: - >>> any([0,1,0]) + >>> any([0, 1, 0]) True - >>> any([0,0,0]) + >>> any([0, 0, 0]) False - >>> any([1,1,1]) + >>> any([1, 1, 1]) True - >>> all([0,1,0]) + >>> all([0, 1, 0]) False - >>> all([0,0,0]) + >>> all([0, 0, 0]) False - >>> all([1,1,1]) + >>> all([1, 1, 1]) True @@ -764,7 +764,7 @@ which defaults to 0, and the interval between numbers, which defaults to 1:: a provided iterable and returns a new iterator that returns its elements from first to last. The new iterator will repeat these elements infinitely. :: - itertools.cycle([1,2,3,4,5]) => + itertools.cycle([1, 2, 3, 4, 5]) => 1, 2, 3, 4, 5, 1, 2, 3, 4, 5, ... :func:`itertools.repeat(elem, [n]) <itertools.repeat>` returns the provided @@ -875,7 +875,7 @@ iterable's results. :: iterators and returns only those elements of *data* for which the corresponding element of *selectors* is true, stopping whenever either one is exhausted:: - itertools.compress([1,2,3,4,5], [True, True, False, False, True]) => + itertools.compress([1, 2, 3, 4, 5], [True, True, False, False, True]) => 1, 2, 5 @@ -1035,7 +1035,7 @@ first calculation. :: Traceback (most recent call last): ... TypeError: reduce() of empty sequence with no initial value - >>> functools.reduce(operator.mul, [1,2,3], 1) + >>> functools.reduce(operator.mul, [1, 2, 3], 1) 6 >>> functools.reduce(operator.mul, [], 1) 1 @@ -1045,9 +1045,9 @@ elements of the iterable. This case is so common that there's a special built-in called :func:`sum` to compute it: >>> import functools, operator - >>> functools.reduce(operator.add, [1,2,3,4], 0) + >>> functools.reduce(operator.add, [1, 2, 3, 4], 0) 10 - >>> sum([1,2,3,4]) + >>> sum([1, 2, 3, 4]) 10 >>> sum([]) 0 @@ -1057,11 +1057,11 @@ write the obvious :keyword:`for` loop:: import functools # Instead of: - product = functools.reduce(operator.mul, [1,2,3], 1) + product = functools.reduce(operator.mul, [1, 2, 3], 1) # You can write: product = 1 - for i in [1,2,3]: + for i in [1, 2, 3]: product *= i A related function is :func:`itertools.accumulate(iterable, func=operator.add) @@ -1069,10 +1069,10 @@ A related function is :func:`itertools.accumulate(iterable, func=operator.add) returning only the final result, :func:`accumulate` returns an iterator that also yields each partial result:: - itertools.accumulate([1,2,3,4,5]) => + itertools.accumulate([1, 2, 3, 4, 5]) => 1, 3, 6, 10, 15 - itertools.accumulate([1,2,3,4,5], operator.mul) => + itertools.accumulate([1, 2, 3, 4, 5], operator.mul) => 1, 2, 6, 24, 120 @@ -1156,7 +1156,7 @@ But it would be best of all if I had simply used a ``for`` loop:: Or the :func:`sum` built-in and a generator expression:: - total = sum(b for a,b in items) + total = sum(b for a, b in items) Many uses of :func:`functools.reduce` are clearer when written as ``for`` loops. |