The implicit conversion of an instance of one type to another during an

operation which involves two arguments of the same type. For example,

{}\code{int(3.15)} converts the floating point number to the integer,

{}\code{3}, but in {}\code{3+4.5}, each argument is of a different type (one

int, one float), and both must be converted to the same type before they can

be added or it will raise a {}\code{TypeError}. Coercion between two

operands can be performed with the {}\code{coerce} builtin function; thus,

{}\code{3+4.5} is equivalent to calling {}\code{operator.add(*coerce(3,

4.5))} and results in {}\code{operator.add(3.0, 4.5)}. Without coercion,

all arguments of even compatible types would have to be normalized to the

same value by the programmer, e.g., {}\code{float(3)+4.5} rather than just

{}\code{3+4.5}.

\index{complex number}

\item[complex number]

An extension of the familiar real number system in which all numbers are

expressed as a sum of a real part and an imaginary part. Imaginary numbers

are real multiples of the imaginary unit (the square root of {}\code{-1}),

often written {}\code{i} in mathematics or {}\code{j} in engineering.

Python has builtin support for complex numbers, which are written with this

latter notation; the imaginary part is written with a {}\code{j} suffix,

e.g., {}\code{3+1j}. To get access to complex equivalents of the

{}\module{math} module, use {}\module{cmath}. Use of complex numbers is a

fairy advanced mathematical feature. If you're not aware of a need for it's

almost certain you can safely ignore them.

A function that returns an iterator. It looks like a normal function except

that values are returned to the caller using a \keyword{yield} statement

instead of a {}\keyword{return} statement. Generator functions often

contain one or more {}\keyword{for} or \keyword{while} loops that

\keyword{yield} elements back to the caller. The function execution is

stopped at the {}\keyword{yield} keyword (returning the result) and is

resumed there when the next element is requested by calling the

\method{next()} method of the returned iterator.

An object with fixed value. Immutable objects are numbers, strings or

a common type. For example, an integer divided by a float will result

Python is an interpreted language, as opposed to a compiled one. This means

that the source files can be run directly without first creating an

executable which is then run. Interpreted languages typically have a

shorter development/debug cycle than compiled ones, though their programs

generally also run more slowly. See also {}\emph{interactive}.