module pixeltable.functions.string
Pixeltable UDFs for StringType.
It closely follows the Pandas pandas.Series.str API.
Example:
udf capitalize()
Return string with its first character capitalized and the rest lowercased.
Equivalent to str.capitalize().
udf casefold()
Return a casefolded copy of string.
Equivalent to str.casefold().
udf center()
Return a centered string of length width.
Equivalent to str.center().
Parameters:
width (Int): Total width of the resulting string.
fillchar (String): Character used for padding.
udf contains()
Test if string contains a substring.
Parameters:
substr (String): string literal or regular expression
case (Bool): if False, ignore case
udf contains_re()
Test if string contains a regular expression pattern.
Parameters:
pattern (String): regular expression pattern
flags (Int): flags for the re module
udf count()
Count occurrences of pattern or regex.
Parameters:
pattern (String): string literal or regular expression
flags (Int): flags for the re module
udf endswith()
Return True if the string ends with the specified suffix, otherwise return False.
Equivalent to str.endswith().
Parameters:
substr (String): string literal
udf fill()
Wraps the single paragraph in string, and returns a single string containing the wrapped paragraph.
Equivalent to textwrap.fill().
Parameters:
width (Int): Maximum line width.
kwargs (Any): Additional keyword arguments to pass to textwrap.fill().
udf find()
Return the lowest index in string where substr is found within the slice s[start:end].
Equivalent to str.find().
Parameters:
substr (String): substring to search for
start (Int): slice start
end (Int | None): slice end
udf findall()
Find all occurrences of a regular expression pattern in string.
Equivalent to re.findall().
Parameters:
pattern (String): regular expression pattern
flags (Int): flags for the re module
Perform string formatting.
Equivalent to str.format().
udf fullmatch()
Determine if string fully matches a regular expression.
Equivalent to re.fullmatch().
Parameters:
pattern (String): regular expression pattern
case (Bool): if False, ignore case
flags (Int): flags for the re module
udf index()
Return the lowest index in string where substr is found within the slice [start:end].
Raises ValueError if substr is not found.
Equivalent to str.index().
Parameters:
substr (String): substring to search for
start (Int): slice start
end (Int | None): slice end
udf isalnum()
Return True if all characters in the string are alphanumeric and there is at least one character, False
otherwise.
Equivalent to [str.isalnum()](https://docs.python.org/3/library/stdtypes.html#str.isalnum
udf isalpha()
Return True if all characters in the string are alphabetic and there is at least one character, False otherwise.
Equivalent to str.isalpha().
udf isascii()
Return True if the string is empty or all characters in the string are ASCII, False otherwise.
Equivalent to str.isascii().
udf isdecimal()
Return True if all characters in the string are decimal characters and there is at least one character, False
otherwise.
Equivalent to str.isdecimal().
udf isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise.
Equivalent to str.isdigit().
udf isidentifier()
Return True if the string is a valid identifier according to the language definition, False otherwise.
Equivalent to str.isidentifier()
udf islower()
Return True if all cased characters in the string are lowercase and there is at least one cased character,
False otherwise.
Equivalent to str.islower()
udf isnumeric()
Return True if all characters in the string are numeric characters, False otherwise.
Equivalent to str.isnumeric()
udf isspace()
Return True if there are only whitespace characters in the string and there is at least one character,
False otherwise.
Equivalent to str.isspace()
udf istitle()
Return True if the string is a titlecased string and there is at least one character, False otherwise.
Equivalent to str.istitle()
udf isupper()
Return True if all cased characters in the string are uppercase and there is at least one cased character,
False otherwise.
Equivalent to str.isupper()
udf join()
Return a string which is the concatenation of the strings in elements.
Equivalent to str.join()
udf len()
Return the number of characters in the string.
Equivalent to len(str)
udf ljust()
Return the string left-justified in a string of length width.
Equivalent to str.ljust()
Parameters:
width (Int): Minimum width of resulting string; additional characters will be filled with character defined in
fillchar.
fillchar (String): Additional character for filling.
udf lower()
Return a copy of the string with all the cased characters converted to lowercase.
Equivalent to str.lower()
udf lstrip()
Return a copy of the string with leading characters removed. The chars argument is a string specifying the set of
characters to be removed. If omitted or None, whitespace characters are removed.
Equivalent to str.lstrip()
Parameters:
chars (String | None): The set of characters to be removed.
udf match()
Determine if string starts with a match of a regular expression
Parameters:
pattern (String): regular expression pattern
case (Bool): if False, ignore case
flags (Int): flags for the re module
udf normalize()
Return the Unicode normal form.
Equivalent to unicodedata.normalize()
Parameters:
form (String): Unicode normal form ('NFC', 'NFKC', 'NFD', 'NFKD')
udf pad()
Pad string up to width
Parameters:
width (Int): Minimum width of resulting string; additional characters will be filled with character defined in
fillchar.
side (String): Side from which to fill resulting string ('left', 'right', 'both')
fillchar (String): Additional character for filling
udf partition()
Splits string at the first occurrence of sep, and returns 3 elements containing the part before the
separator, the separator itself, and the part after the separator. If the separator is not found, return 3 elements
containing string itself, followed by two empty strings.
udf removeprefix()
Remove prefix. If the prefix is not present, returns string.
udf removesuffix()
Remove suffix. If the suffix is not present, returns string.
udf repeat()
Repeat string n times.
udf replace()
Replace occurrences of substr with repl.
Equivalent to str.replace().
Parameters:
substr (String): string literal
repl (String): replacement string
n (Int | None): number of replacements to make (if None, replace all occurrences)
udf replace_re()
Replace occurrences of a regular expression pattern with repl.
Equivalent to re.sub().
Parameters:
pattern (String): regular expression pattern
repl (String): replacement string
n (Int | None): number of replacements to make (if None, replace all occurrences)
flags (Int): flags for the re module
udf reverse()
Return a reversed copy of the string.
Equivalent to str[::-1].
udf rfind()
Return the highest index where substr is found, such that substr is contained within [start:end].
Equivalent to str.rfind().
Parameters:
substr (String): substring to search for
start (Int | None): slice start
end (Int | None): slice end
udf rindex()
Return the highest index where substr is found, such that substr is contained within [start:end].
Raises ValueError if substr is not found.
Equivalent to str.rindex().
udf rjust()
Return the string right-justified in a string of length width.
Equivalent to str.rjust().
Parameters:
width (Int): Minimum width of resulting string.
fillchar (String): Additional character for filling.
udf rpartition()
This method splits string at the last occurrence of sep, and returns a list containing the part before the
separator, the separator itself, and the part after the separator.
udf rstrip()
Return a copy of string with trailing characters removed.
Equivalent to str.rstrip().
Parameters:
chars (String | None): The set of characters to be removed. If omitted or None, whitespace characters are removed.
udf slice()
Return a slice.
Parameters:
start (Int | None): slice start
stop (Int | None): slice end
step (Int | None): slice step
udf slice_replace()
Replace a positional slice with another value.
Parameters:
start (Int | None): slice start
stop (Int | None): slice end
repl (String | None): replacement value
udf startswith()
Return True if string starts with substr, otherwise return False.
Equivalent to str.startswith().
Parameters:
substr (String): string literal
udf strip()
Return a copy of string with leading and trailing characters removed.
Equivalent to str.strip().
Parameters:
chars (String | None): The set of characters to be removed. If omitted or None, whitespace characters are removed.
udf swapcase()
Return a copy of string with uppercase characters converted to lowercase and vice versa.
Equivalent to str.swapcase().
udf title()
Return a titlecased version of string, i.e. words start with uppercase characters, all remaining cased characters
are lowercase.
Equivalent to str.title().
udf upper()
Return a copy of string converted to uppercase.
Equivalent to str.upper().
udf wrap()
Wraps the single paragraph in string so every line is at most width characters long.
Returns a list of output lines, without final newlines.
Equivalent to textwrap.fill().
Parameters:
width (Int): Maximum line width.
kwargs (Any): Additional keyword arguments to pass to textwrap.fill().
Last modified on June 12, 2026