array
This module defines a new object type which can efficiently represent an array of basic values: characters, integers, floating point numbers. Arrays are sequence types and behave very much like lists, except that the type of objects stored in them is constrained. The type is specified at object creation time by using a type code, which is a single character. The following type codes are defined:
The actual representation of values is determined by the machine
architecture (strictly speaking, by the C implementation). The actual
size can be accessed through the itemsize attribute. The values
stored for 'L'
and 'I'
items will be represented as
Python long integers when retrieved, because Python's plain integer
type can't represent the full range of C's unsigned (long) integers.
See also built-in module struct
.
The module defines the following function:
fromlist()
or fromstring()
method (see below) to add
initial items to the array.
Array objects support the following data items and methods:
(address, varlength)
giving the current
memory address and the length in bytes of the buffer used to hold
array's contents. This is occasionally useful when working with
low-level (and inherently unsafe) I/O interfaces that require memory
addresses, such as certain ioctl
operations. The returned
numbers are valid as long as the array exists and no length-changing
operations are applied to it.
EOFError
is raised, but the items that were
available are still inserted into the array. f must be a real
built-in file object; something else with a read()
method won't
do.
for x in list: a.append(x)
except that if there is a type error, the array is unchanged.
fromfile()
method).
tofile()
method.)
When an array object is printed or converted to a string, it is
represented as array(typecode, initializer)
. The
initializer is omitted if the array is empty, otherwise it is a
string if the typecode is 'c'
, otherwise it is a list of
numbers. The string is guaranteed to be able to be converted back to
an array with the same type and value using reverse quotes
(``
). Examples:
array('l') array('c', 'hello world') array('l', [1, 2, 3, 4, 5]) array('d', [1.0, 2.0, 3.14])
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