String operations

This module provides a set of vectorized string operations for arrays of type numpy.string_ or numpy.unicode_. All of them are based on the string methods in the Python standard library.

String operations

`add`(x1, x2)	Return element-wise string concatenation for two arrays of str or unicode.
`multiply`(a, i)	Return (a * i), that is string multiple concatenation, element-wise.
`mod`(a, values)	Return (a % i), that is pre-Python 2.6 string formatting (iterpolation), element-wise for a pair of array_likes of str or unicode.
`capitalize`(a)	Return a copy of `a` with only the first character of each element capitalized.
`center`(a, width[, fillchar])	Return a copy of `a` with its elements centered in a string of length `width`.
`decode`(a[, encoding, errors])	Calls `str.decode` element-wise.
`encode`(a[, encoding, errors])	Calls `str.encode` element-wise.
`join`(sep, seq)	Return a string which is the concatenation of the strings in the sequence `seq`.
`ljust`(a, width[, fillchar])	Return an array with the elements of `a` left-justified in a string of length `width`.
`lower`(a)	Return an array with the elements converted to lowercase.
`lstrip`(a[, chars])	For each element in `a`, return a copy with the leading characters removed.
`partition`(a, sep)	Partition each element in `a` around `sep`.
`replace`(a, old, new[, count])	For each element in `a`, return a copy of the string with all occurrences of substring `old` replaced by `new`.
`rjust`(a, width[, fillchar])	Return an array with the elements of `a` right-justified in a string of length `width`.
`rpartition`(a, sep)	Partition (split) each element around the right-most separator.
`rsplit`(a[, sep, maxsplit])	For each element in `a`, return a list of the words in the string, using `sep` as the delimiter string.
`rstrip`(a[, chars])	For each element in `a`, return a copy with the trailing characters removed.
`split`(a[, sep, maxsplit])	For each element in `a`, return a list of the words in the string, using `sep` as the delimiter string.
`splitlines`(a[, keepends])	For each element in `a`, return a list of the lines in the element, breaking at line boundaries.
`strip`(a[, chars])	For each element in `a`, return a copy with the leading and trailing characters removed.
`swapcase`(a)	Return element-wise a copy of the string with uppercase characters converted to lowercase and vice versa.
`title`(a)	Return element-wise title cased version of string or unicode.
`translate`(a, table[, deletechars])	For each element in `a`, return a copy of the string where all characters occurring in the optional argument `deletechars` are removed, and the remaining characters have been mapped through the given translation table.
`upper`(a)	Return an array with the elements converted to uppercase.
`zfill`(a, width)	Return the numeric string left-filled with zeros

Comparison

Unlike the standard numpy comparison operators, the ones in the char module strip trailing whitespace characters before performing the comparison.

`equal`(x1, x2)	Return (x1 == x2) element-wise.
`not_equal`(x1, x2)	Return (x1 != x2) element-wise.
`greater_equal`(x1, x2)	Return (x1 >= x2) element-wise.
`less_equal`(x1, x2)	Return (x1 <= x2) element-wise.
`greater`(x1, x2)	Return (x1 > x2) element-wise.
`less`(x1, x2)	Return (x1 < x2) element-wise.

String information

`count`(a, sub[, start, end])	Returns an array with the number of non-overlapping occurrences of substring `sub` in the range [`start`, `end`].
`find`(a, sub[, start, end])	For each element, return the lowest index in the string where substring `sub` is found.
`index`(a, sub[, start, end])	Like `find`, but raises `ValueError` when the substring is not found.
`isalpha`(a)	Returns true for each element if all characters in the string are alphabetic and there is at least one character, false otherwise.
`isdecimal`(a)	For each element, return True if there are only decimal characters in the element.
`isdigit`(a)	Returns true for each element if all characters in the string are digits and there is at least one character, false otherwise.
`islower`(a)	Returns true for each element if all cased characters in the string are lowercase and there is at least one cased character, false otherwise.
`isnumeric`(a)	For each element, return True if there are only numeric characters in the element.
`isspace`(a)	Returns true for each element if there are only whitespace characters in the string and there is at least one character, false otherwise.
`istitle`(a)	Returns true for each element if the element is a titlecased string and there is at least one character, false otherwise.
`isupper`(a)	Returns true for each element if all cased characters in the string are uppercase and there is at least one character, false otherwise.
`rfind`(a, sub[, start, end])	For each element in `a`, return the highest index in the string where substring `sub` is found, such that `sub` is contained within [`start`, `end`].
`rindex`(a, sub[, start, end])	Like `rfind`, but raises `ValueError` when the substring `sub` is not found.
`startswith`(a, prefix[, start, end])	Returns a boolean array which is `True` where the string element in `a` starts with `prefix`, otherwise `False`.

Convenience class

chararray Provides a convenient view on arrays of string and unicode values.

Links:

https://docs.scipy.org/doc/numpy-1.11.0/reference/routines.char.html

doc_NumPy

2017-01-10 18:20:52

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