|buffer=None, itemsize=None, shape=None, byteoffset=0, bytestride=None, kind=CharArray)|
arrayis, for most practical purposes, all a user needs to know to construct a character array.
The first argument,
buffer, may be any one of the following:
None (default). The constructor will allocate a writeable memory
buffer which will be uninitialized. The user must assign valid data before
trying to read the contents or before writing the character array to a disk
(2) a Python string containing binary data. For example:
>>> print str.array('abcdefg'*10, itemsize=10) ['abcdefgabc', 'defgabcdef', 'gabcdefgab', 'cdefgabcde', 'fgabcdefga', 'bcdefgabcd', 'efgabcdefg']
(3) a Python file object for an open file. The data will be copied from the file, starting at the current position of the read pointer.
(4) a character array. This results in a deep copy of the input character
array; any other arguments to
array() will be silently ignored.
>>> print str.array(s) ['abcdefgabc', 'defgabcdef', 'gabcdefgab', 'cdefgabcde', 'fgabcdefga', 'bcdefgabcd', 'efgabcdefg']
(5) a nested sequence of strings. The sequence nesting implies the shape of the string array unless shape is specified.
>>> print str.array([['Smith', 'Johnson'], ['Williams', 'Miller']]) [['Smith', 'Johnson'], ['Williams', 'Miller']]
itemsize can be used to increase or decrease the fixed size of an
array element relative to the natural itemsize implied by any literal data
specified by the
>>> print str.array([['Smith', 'Johnson'], ['Williams', 'Miller']], itemsize=2) [['Sm', 'Jo'], ['Wi', 'Mi']]) >>> print str.array([['Smith', 'Johnson'], ['Williams', 'Miller']], itemsize=20) [['Smith', 'Johnson'], ['Williams', 'Miller']]
shape is the shape of the character array. It can be an integer, in
which case it is equivalent to the number of rows in a table. It can
also be a tuple implying the character array is an N-D array with fixed
length strings as its elements.
shape should be consistent with
the number of elements implied by the data buffer and itemsize.
byteoffset indicates an offset, specified in bytes, from the start
of the array buffer to where the array data actually begins.
byteoffset enables the character array to be offset from the
beginning of a table record. This is mainly useful for implementing
bytestride indicates the separation, specified in bytes, between
successive elements in the last dimension of the character array.
bytestride is used in the implementation of record arrays to space
character array elements with the size of the total record rather than the
size of a single string.
kind is used to specify the class of the created array, and should be
CharArray, or a subclass of either.
|n, format, itemsize=32)|
num2charformats the numarray
nusing the Python string format
formatand stores the result in a character array with the specified
>>> num2char(num.arange(0.0,5), '%2.2f') CharArray(['0.00', '1.00', '2.00', '3.00', '4.00'])
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