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 Calls str.zfill element-wise.

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.

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