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array
This module defines an 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.
Classes
array
array(typecode [, initializer]) -> array
Return a new array whose items are restricted by typecode, and
initialized from the optional initializer value, which must be a list,
string or iterable over elements of the appropriate type.
Arrays represent basic values and behave very much like lists, except
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:
Type code C Type Minimum size in bytes
'b' signed integer 1
'B' unsigned integer 1
'u' Unicode character 2 (see note)
'h' signed integer 2
'H' unsigned integer 2
'i' signed integer 2
'I' unsigned integer 2
'l' signed integer 4
'L' unsigned integer 4
'q' signed integer 8 (see note)
'Q' unsigned integer 8 (see note)
'f' floating point 4
'd' floating point 8
NOTE: The 'u' typecode corresponds to Python's unicode character. On
narrow builds this is 2-bytes on wide builds this is 4-bytes.
NOTE: The 'q' and 'Q' type codes are only available if the platform
C compiler used to build Python supports 'long long', or, on Windows,
'__int64'.
Methods:
append() -- append a new item to the end of the array
buffer_info() -- return information giving the current memory info
byteswap() -- byteswap all the items of the array
count() -- return number of occurrences of an object
extend() -- extend array by appending multiple elements from an iterable
fromfile() -- read items from a file object
fromlist() -- append items from the list
frombytes() -- append items from the string
index() -- return index of first occurrence of an object
insert() -- insert a new item into the array at a provided position
pop() -- remove and return item (default last)
remove() -- remove first occurrence of an object
reverse() -- reverse the order of the items in the array
tofile() -- write all items to a file object
tolist() -- return the array converted to an ordinary list
tobytes() -- return the array converted to a string
Attributes:
typecode -- the typecode character used to create the array
itemsize -- the length in bytes of one array item
append(self, v, /)
Append new value v to the end of the array.
buffer_info(self, /)
Return a tuple (address, length) giving the current memory address and the length in items of the buffer used to hold array's contents.
The length should be multiplied by the itemsize attribute to calculate
the buffer length in bytes.
byteswap(self, /)
Byteswap all items of the array.
If the items in the array are not 1, 2, 4, or 8 bytes in size, RuntimeError is
raised.
count(self, v, /)
Return number of occurrences of v in the array.
extend(self, bb, /)
Append items to the end of the array.
frombytes(self, buffer, /)
Appends items from the string, interpreting it as an array of machine values, as if it had been read from a file using the fromfile() method.
fromfile(self, f, n, /)
Read n objects from the file object f and append them to the end of the array.
fromlist(self, list, /)
Append items to array from list.
fromunicode(self, ustr, /)
Extends this array with data from the unicode string ustr.
The array must be a unicode type array; otherwise a ValueError is raised.
Use array.frombytes(ustr.encode(...)) to append Unicode data to an array of
some other type.
index(self, v, /)
Return index of first occurrence of v in the array.
insert(self, i, v, /)
Insert a new item v into the array before position i.
pop(self, i=-1, /)
Return the i-th element and delete it from the array.
i defaults to -1.
remove(self, v, /)
Remove the first occurrence of v in the array.
reverse(self, /)
Reverse the order of the items in the array.
tobytes(self, /)
Convert the array to an array of machine values and return the bytes representation.
tofile(self, f, /)
Write all items (as machine values) to the file object f.
tolist(self, /)
Convert array to an ordinary list with the same items.
tounicode(self, /)
Extends this array with data from the unicode string ustr.
Convert the array to a unicode string. The array must be a unicode type array;
otherwise a ValueError is raised. Use array.tobytes().decode() to obtain a
unicode string from an array of some other type.
itemsize = <attribute 'itemsize' of 'array.array' objects>
the size, in bytes, of one array item
typecode = <attribute 'typecode' of 'array.array' objects>
the typecode character used to create the array
array
array(typecode [, initializer]) -> array
Return a new array whose items are restricted by typecode, and
initialized from the optional initializer value, which must be a list,
string or iterable over elements of the appropriate type.
Arrays represent basic values and behave very much like lists, except
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:
Type code C Type Minimum size in bytes
'b' signed integer 1
'B' unsigned integer 1
'u' Unicode character 2 (see note)
'h' signed integer 2
'H' unsigned integer 2
'i' signed integer 2
'I' unsigned integer 2
'l' signed integer 4
'L' unsigned integer 4
'q' signed integer 8 (see note)
'Q' unsigned integer 8 (see note)
'f' floating point 4
'd' floating point 8
NOTE: The 'u' typecode corresponds to Python's unicode character. On
narrow builds this is 2-bytes on wide builds this is 4-bytes.
NOTE: The 'q' and 'Q' type codes are only available if the platform
C compiler used to build Python supports 'long long', or, on Windows,
'__int64'.
Methods:
append() -- append a new item to the end of the array
buffer_info() -- return information giving the current memory info
byteswap() -- byteswap all the items of the array
count() -- return number of occurrences of an object
extend() -- extend array by appending multiple elements from an iterable
fromfile() -- read items from a file object
fromlist() -- append items from the list
frombytes() -- append items from the string
index() -- return index of first occurrence of an object
insert() -- insert a new item into the array at a provided position
pop() -- remove and return item (default last)
remove() -- remove first occurrence of an object
reverse() -- reverse the order of the items in the array
tofile() -- write all items to a file object
tolist() -- return the array converted to an ordinary list
tobytes() -- return the array converted to a string
Attributes:
typecode -- the typecode character used to create the array
itemsize -- the length in bytes of one array item
append(self, v, /)
Append new value v to the end of the array.
buffer_info(self, /)
Return a tuple (address, length) giving the current memory address and the length in items of the buffer used to hold array's contents.
The length should be multiplied by the itemsize attribute to calculate
the buffer length in bytes.
byteswap(self, /)
Byteswap all items of the array.
If the items in the array are not 1, 2, 4, or 8 bytes in size, RuntimeError is
raised.
count(self, v, /)
Return number of occurrences of v in the array.
extend(self, bb, /)
Append items to the end of the array.
frombytes(self, buffer, /)
Appends items from the string, interpreting it as an array of machine values, as if it had been read from a file using the fromfile() method.
fromfile(self, f, n, /)
Read n objects from the file object f and append them to the end of the array.
fromlist(self, list, /)
Append items to array from list.
fromunicode(self, ustr, /)
Extends this array with data from the unicode string ustr.
The array must be a unicode type array; otherwise a ValueError is raised.
Use array.frombytes(ustr.encode(...)) to append Unicode data to an array of
some other type.
index(self, v, /)
Return index of first occurrence of v in the array.
insert(self, i, v, /)
Insert a new item v into the array before position i.
pop(self, i=-1, /)
Return the i-th element and delete it from the array.
i defaults to -1.
remove(self, v, /)
Remove the first occurrence of v in the array.
reverse(self, /)
Reverse the order of the items in the array.
tobytes(self, /)
Convert the array to an array of machine values and return the bytes representation.
tofile(self, f, /)
Write all items (as machine values) to the file object f.
tolist(self, /)
Convert array to an ordinary list with the same items.
tounicode(self, /)
Extends this array with data from the unicode string ustr.
Convert the array to a unicode string. The array must be a unicode type array;
otherwise a ValueError is raised. Use array.tobytes().decode() to obtain a
unicode string from an array of some other type.
itemsize = <attribute 'itemsize' of 'array.array' objects>
the size, in bytes, of one array item
typecode = <attribute 'typecode' of 'array.array' objects>
the typecode character used to create the array
Other members
typecodes = 'bBuhHiIlLqQfd'