A scalar function maps values from a domain to a range. When we look at the math.sqrt() function, as an example, we're looking at a mapping from the float value, x, to another float value, y = sqrt(x), such that
. The domain is limited to positive values. The mapping can be done via a calculation or table interpolation.
The map() function expresses a similar concept; it maps values from one collection to create another collection. It assures that the given function is used to map each individual item from the domain collection to the range collection-the ideal way to apply a built-in function to a collection of data.
Our first example involves parsing a block of text to get the sequence of numbers. Let's say we have the following chunk of text:
>>> text= """\
... 2 3 5 7 11 13 17 19 23 29
... 31 37 41 43 47 53 59 61 67 71
... 73 79 83 89 97 101 103 107 109 113
... 127...