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Don't introduce map(None, ...) in the tutorial. In practice, zip() is
usually preferred.
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@ -1836,19 +1836,14 @@ cubes:
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More than one sequence may be passed; the function must then have as
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More than one sequence may be passed; the function must then have as
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many arguments as there are sequences and is called with the
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many arguments as there are sequences and is called with the
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corresponding item from each sequence (or \code{None} if some sequence
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corresponding item from each sequence (or \code{None} if some sequence
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is shorter than another). If \code{None} is passed for the function,
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is shorter than another). For example:
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a function returning its argument(s) is substituted.
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Combining these two special cases, we see that
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\samp{map(None, \var{list1}, \var{list2})} is a convenient way of
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turning a pair of lists into a list of pairs. For example:
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\begin{verbatim}
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\begin{verbatim}
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>>> seq = range(8)
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>>> seq = range(8)
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>>> def square(x): return x*x
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>>> def add(x, y): return x+y
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...
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...
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>>> map(None, seq, map(square, seq))
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>>> map(add, seq, seq)
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[(0, 0), (1, 1), (2, 4), (3, 9), (4, 16), (5, 25), (6, 36), (7, 49)]
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[0, 2, 4, 6, 8, 10, 12, 14]
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\end{verbatim}
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\end{verbatim}
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\samp{reduce(\var{func}, \var{sequence})} returns a single value
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\samp{reduce(\var{func}, \var{sequence})} returns a single value
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