Core Python Programming

11.7.2. Built-in Functions: apply(), filter(), map(), reduce()

In this section, we will look at the apply(), filter(), map(), and reduce() built-in functions as well as give some examples to show how they can be used. These functions provide the functional programming features found in Python. A summary of these functions is given in Table 11.1. All take a function object to somehow invoke.

Table 11.1. Functional Programming Built-in Functions

Built-in Function	Description
apply(func[, nkw][, kw])	call func with optional arguments, nkw for non-keyword arguments and kw for keyword arguments; the return value is the return value of the function call
filter(func, seq)	invokes Boolean function func iteratively over each element of seq; returns a sequence ...