Built-in Numeric Tools

Besides the built-in number literals shown in Table 5-1, Python provides a set of tools for processing number objects:

Expression operators

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+, -, *, /, >>, **, &, etc.

Built-in mathematical functions

pow, abs, round, int, hex, bin, etc.

Utility modules

random, math, etc.

We’ll meet all of these as we go along.

Although numbers are primarily processed with expressions, built-ins, and modules, they also have a handful of type-specific methods today, which we’ll meet in this chapter as well. Floating-point numbers, for example, have an as_integer_ratio method that is useful for the fraction number type, and an is_integer method to test if the number is an integer. Integers have various attributes, including a new bit_length method in the upcoming Python 3.1 release that gives the number of bits necessary to represent the object’s value. Moreover, as part collection and part number, sets also support both methods and expressions.

Since expressions are the most essential tool for most number types, though, let’s turn to them next.