Source code for openpyxl.utils.inference

# Copyright (c) 2010-2019 openpyxl

"""
Type inference functions
"""
import datetime
import re

from openpyxl.styles import numbers

PERCENT_REGEX = re.compile(r'^(?P<number>\-?[0-9]*\.?[0-9]*\s?)\%$')
TIME_REGEX = re.compile(r"""
^(?: # HH:MM and HH:MM:SS
(?P<hour>[0-1]{0,1}[0-9]{2}):
(?P<minute>[0-5][0-9]):?
(?P<second>[0-5][0-9])?$)
|
^(?: # MM:SS.
([0-5][0-9]):
([0-5][0-9])?\.
(?P<microsecond>\d{1,6}))
""", re.VERBOSE)
NUMBER_REGEX = re.compile(r'^-?([\d]|[\d]+\.[\d]*|\.[\d]+|[1-9][\d]+\.?[\d]*)((E|e)[-+]?[\d]+)?$')


[docs]def cast_numeric(value): """Explicity convert a string to a numeric value""" if NUMBER_REGEX.match(value): try: return int(value) except ValueError: return float(value)
[docs]def cast_percentage(value): """Explicitly convert a string to numeric value and format as a percentage""" match = PERCENT_REGEX.match(value) if match: return float(match.group('number')) / 100
[docs]def cast_time(value): """Explicitly convert a string to a number and format as datetime or time""" match = TIME_REGEX.match(value) if match: if match.group("microsecond") is not None: value = value[:12] pattern = "%M:%S.%f" #fmt = numbers.FORMAT_DATE_TIME5 elif match.group('second') is None: #fmt = numbers.FORMAT_DATE_TIME3 pattern = "%H:%M" else: pattern = "%H:%M:%S" #fmt = numbers.FORMAT_DATE_TIME6 value = datetime.datetime.strptime(value, pattern) return value.time()