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Source code for temporal.datetime_math

"""
Functions for mathematical datetime operations

(C) 2011-2013 by the GRASS Development Team
This program is free software under the GNU General Public
License (>=v2). Read the file COPYING that comes with GRASS
for details.

:authors: Soeren Gebbert
"""
from datetime import datetime, timedelta
from .core import get_tgis_message_interface
import copy

try:
    import dateutil.parser as parser
    has_dateutil = True
except:
    has_dateutil = False

DAY_IN_SECONDS = 86400
SECOND_AS_DAY = 1.1574074074074073e-05

###############################################################################


[docs]def relative_time_to_time_delta(value): """Convert the double value representing days into a timedelta object. """ days = int(value) seconds = value % 1 seconds = round(seconds * DAY_IN_SECONDS) return timedelta(days, seconds) ###############################################################################
[docs]def time_delta_to_relative_time(delta): """Convert the time delta into a double value, representing days. """ return float(delta.days) + float(delta.seconds * SECOND_AS_DAY) ###############################################################################
[docs]def relative_time_to_time_delta_seconds(value): """Convert the double value representing seconds into a timedelta object. """ days = (value / 86400) seconds = int(value % 86400) return timedelta(days, seconds) ###############################################################################
[docs]def time_delta_to_relative_time_seconds(delta): """Convert the time delta into a double value, representing seconds. """ return float(delta.days * DAY_IN_SECONDS) + float(delta.seconds) ###############################################################################
[docs]def decrement_datetime_by_string(mydate, increment, mult=1): """Return a new datetime object decremented with the provided relative dates specified as string. Additional a multiplier can be specified to multiply the increment before adding to the provided datetime object. Usage: .. code-block:: python >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "31 days" >>> decrement_datetime_by_string(dt, string) datetime.datetime(2000, 12, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "1 month" >>> decrement_datetime_by_string(dt, string) datetime.datetime(2000, 12, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "2 month" >>> decrement_datetime_by_string(dt, string) datetime.datetime(2000, 11, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "24 months" >>> decrement_datetime_by_string(dt, string) datetime.datetime(1999, 1, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "48 months" >>> decrement_datetime_by_string(dt, string) datetime.datetime(1997, 1, 1, 0, 0) >>> dt = datetime(2001, 6, 1, 0, 0, 0) >>> string = "5 months" >>> decrement_datetime_by_string(dt, string) datetime.datetime(2001, 1, 1, 0, 0) >>> dt = datetime(2001, 6, 1, 0, 0, 0) >>> string = "7 months" >>> decrement_datetime_by_string(dt, string) datetime.datetime(2000, 11, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "1 year" >>> decrement_datetime_by_string(dt, string) datetime.datetime(2000, 1, 1, 0, 0) :param mydate: A datetime object to incremented :param increment: A string providing increment information: The string may include comma separated values of type seconds, minutes, hours, days, weeks, months and years Example: Increment the datetime 2001-01-01 00:00:00 with "60 seconds, 4 minutes, 12 hours, 10 days, 1 weeks, 5 months, 1 years" will result in the datetime 2003-02-18 12:05:00 :param mult: A multiplier, default is 1 :return: The new datetime object or none in case of an error """ return modify_datetime_by_string(mydate, increment, mult, sign=int(-1)) ###############################################################################
[docs]def increment_datetime_by_string(mydate, increment, mult=1): """Return a new datetime object incremented with the provided relative dates specified as string. Additional a multiplier can be specified to multiply the increment before adding to the provided datetime object. Usage: .. code-block:: python >>> dt = datetime(2001, 9, 1, 0, 0, 0) >>> string = "60 seconds, 4 minutes, 12 hours, 10 days, 1 weeks, 5 months, 1 years" >>> increment_datetime_by_string(dt, string) datetime.datetime(2003, 2, 18, 12, 5) >>> dt = datetime(2001, 11, 1, 0, 0, 0) >>> string = "1 months" >>> increment_datetime_by_string(dt, string) datetime.datetime(2001, 12, 1, 0, 0) >>> dt = datetime(2001, 11, 1, 0, 0, 0) >>> string = "13 months" >>> increment_datetime_by_string(dt, string) datetime.datetime(2002, 12, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "72 months" >>> increment_datetime_by_string(dt, string) datetime.datetime(2007, 1, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "72 months" >>> increment_datetime_by_string(dt, string) datetime.datetime(2007, 1, 1, 0, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "5 minutes" >>> increment_datetime_by_string(dt, string) datetime.datetime(2001, 1, 1, 0, 5) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "49 hours" >>> increment_datetime_by_string(dt, string) datetime.datetime(2001, 1, 3, 1, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "3600 seconds" >>> increment_datetime_by_string(dt, string) datetime.datetime(2001, 1, 1, 1, 0) >>> dt = datetime(2001, 1, 1, 0, 0, 0) >>> string = "30 days" >>> increment_datetime_by_string(dt, string) datetime.datetime(2001, 1, 31, 0, 0) :param mydate: A datetime object to incremented :param increment: A string providing increment information: The string may include comma separated values of type seconds, minutes, hours, days, weeks, months and years Example: Increment the datetime 2001-01-01 00:00:00 with "60 seconds, 4 minutes, 12 hours, 10 days, 1 weeks, 5 months, 1 years" will result in the datetime 2003-02-18 12:05:00 :param mult: A multiplier, default is 1 :return: The new datetime object or none in case of an error """ return modify_datetime_by_string(mydate, increment, mult, sign=int(1)) ###############################################################################
[docs]def modify_datetime_by_string(mydate, increment, mult=1, sign=1): """Return a new datetime object incremented with the provided relative dates specified as string. Additional a multiplier can be specified to multiply the increment before adding to the provided datetime object. :param mydate: A datetime object to incremented :param increment: A string providing increment information: The string may include comma separated values of type seconds, minutes, hours, days, weeks, months and years Example: Increment the datetime 2001-01-01 00:00:00 with "60 seconds, 4 minutes, 12 hours, 10 days, 1 weeks, 5 months, 1 years" will result in the datetime 2003-02-18 12:05:00 :param mult: A multiplier, default is 1 :param sign: Choose 1 for positive sign (incrementing) or -1 for negative sign (decrementing). :return: The new datetime object or none in case of an error """ sign = int(sign) if sign != 1 and sign != -1: return None if increment: seconds = 0 minutes = 0 hours = 0 days = 0 weeks = 0 months = 0 years = 0 inclist = [] # Split the increment string incparts = increment.split(",") for incpart in incparts: inclist.append(incpart.strip().split(" ")) for inc in inclist: msgr = get_tgis_message_interface() if len(inc) < 2: msgr.error(_("Wrong increment format: %s") % (increment)) return None if inc[1].find("seconds") >= 0 or inc[1].find("second") >= 0: seconds = sign * mult * int(inc[0]) elif inc[1].find("minutes") >= 0 or inc[1].find("minute") >= 0: minutes = sign * mult * int(inc[0]) elif inc[1].find("hours") >= 0 or inc[1].find("hour") >= 0: hours = sign * mult * int(inc[0]) elif inc[1].find("days") >= 0 or inc[1].find("day") >= 0: days = sign * mult * int(inc[0]) elif inc[1].find("weeks") >= 0 or inc[1].find("week") >= 0: weeks = sign * mult * int(inc[0]) elif inc[1].find("months") >= 0 or inc[1].find("month") >= 0: months = sign * mult * int(inc[0]) elif inc[1].find("years") >= 0 or inc[1].find("year") >= 0: years = sign * mult * int(inc[0]) else: msgr.error(_("Wrong increment format: %s") % (increment)) return None return modify_datetime(mydate, years, months, weeks, days, hours, minutes, seconds) return mydate ###############################################################################
[docs]def modify_datetime(mydate, years=0, months=0, weeks=0, days=0, hours=0, minutes=0, seconds=0): """Return a new datetime object incremented with the provided relative dates and times""" tdelta_seconds = timedelta(seconds=seconds) tdelta_minutes = timedelta(minutes=minutes) tdelta_hours = timedelta(hours=hours) tdelta_days = timedelta(days=days) tdelta_weeks = timedelta(weeks=weeks) tdelta_months = timedelta(0) tdelta_years = timedelta(0) if months > 0: # Compute the actual number of days in the month to add as timedelta year = mydate.year month = mydate.month all_months = int(months) + int(month) years_to_add = int(all_months / 12.001) residual_months = all_months - (years_to_add * 12) # Make a deep copy of the datetime object dt1 = copy.copy(mydate) # Make sure the month starts with a 1 if residual_months == 0: residual_months = 1 try: dt1 = dt1.replace(year=year + years_to_add, month=residual_months) except: raise tdelta_months = dt1 - mydate elif months < 0: # Compute the actual number of days in the month to add as timedelta year = mydate.year month = mydate.month years_to_remove = 0 all_months = int(months) + int(month) if all_months <= 0: years_to_remove = abs(int(all_months / 12.001)) residual_months = all_months + (years_to_remove * 12) years_to_remove += 1 else: residual_months = all_months # Make a deep copy of the datetime object dt1 = copy.copy(mydate) # Correct the months if residual_months <= 0: residual_months += 12 try: dt1 = dt1.replace(year=year - years_to_remove, month=residual_months) except: raise tdelta_months = dt1 - mydate if years != 0: # Make a deep copy of the datetime object dt1 = copy.copy(mydate) # Compute the number of days dt1 = dt1.replace(year=mydate.year + int(years)) tdelta_years = dt1 - mydate return mydate + tdelta_seconds + tdelta_minutes + tdelta_hours + \ tdelta_days + tdelta_weeks + tdelta_months + tdelta_years ###############################################################################
[docs]def adjust_datetime_to_granularity(mydate, granularity): """Modify the datetime object to fit the given granularity - Years will start at the first of Januar - Months will start at the first day of the month - Days will start at the first Hour of the day - Hours will start at the first minute of an hour - Minutes will start at the first second of a minute Usage: .. code-block:: python >>> dt = datetime(2001, 8, 8, 12,30,30) >>> adjust_datetime_to_granularity(dt, "5 seconds") datetime.datetime(2001, 8, 8, 12, 30, 30) >>> adjust_datetime_to_granularity(dt, "20 minutes") datetime.datetime(2001, 8, 8, 12, 30) >>> adjust_datetime_to_granularity(dt, "20 minutes") datetime.datetime(2001, 8, 8, 12, 30) >>> adjust_datetime_to_granularity(dt, "3 hours") datetime.datetime(2001, 8, 8, 12, 0) >>> adjust_datetime_to_granularity(dt, "5 days") datetime.datetime(2001, 8, 8, 0, 0) >>> adjust_datetime_to_granularity(dt, "2 weeks") datetime.datetime(2001, 8, 6, 0, 0) >>> adjust_datetime_to_granularity(dt, "6 months") datetime.datetime(2001, 8, 1, 0, 0) >>> adjust_datetime_to_granularity(dt, "2 years") datetime.datetime(2001, 1, 1, 0, 0) >>> adjust_datetime_to_granularity(dt, "2 years, 3 months, 5 days, 3 hours, 3 minutes, 2 seconds") datetime.datetime(2001, 8, 8, 12, 30, 30) >>> adjust_datetime_to_granularity(dt, "3 months, 5 days, 3 minutes") datetime.datetime(2001, 8, 8, 12, 30) >>> adjust_datetime_to_granularity(dt, "3 weeks, 5 days") datetime.datetime(2001, 8, 8, 0, 0) """ if granularity: has_seconds = False has_minutes = False has_hours = False has_days = False has_weeks = False has_months = False has_years = False seconds = mydate.second minutes = mydate.minute hours = mydate.hour days = mydate.day weekday = mydate.weekday() months = mydate.month years = mydate.year granlist = [] # Split the increment string granparts = granularity.split(",") for granpart in granparts: granlist.append(granpart.strip().split(" ")) for inc in granlist: if inc[1].find("seconds") >= 0 or inc[1].find("second") >= 0: has_seconds = True elif inc[1].find("minutes") >= 0 or inc[1].find("minute") >= 0: has_minutes = True elif inc[1].find("hours") >= 0 or inc[1].find("hour") >= 0: has_hours = True elif inc[1].find("days") >= 0 or inc[1].find("day") >= 0: has_days = True elif inc[1].find("weeks") >= 0 or inc[1].find("week") >= 0: has_weeks = True elif inc[1].find("months") >= 0 or inc[1].find("month") >= 0: has_months = True elif inc[1].find("years") >= 0 or inc[1].find("year") >= 0: has_years = True else: msgr = get_tgis_message_interface() msgr.error(_("Wrong granularity format: %s") % (granularity)) return None if has_seconds: pass elif has_minutes: # Start at 0 seconds seconds = 0 elif has_hours: # Start at 0 minutes and seconds seconds = 0 minutes = 0 elif has_days: # Start at 0 hours, minutes and seconds seconds = 0 minutes = 0 hours = 0 elif has_weeks: # Start at the first day of the week (Monday) at 00:00:00 seconds = 0 minutes = 0 hours = 0 if days > weekday: days = days - weekday # this needs to be fixed else: days = days + weekday # this needs to be fixed elif has_months: # Start at the first day of the month at 00:00:00 seconds = 0 minutes = 0 hours = 0 days = 1 elif has_years: # Start at the first day of the first month at 00:00:00 seconds = 0 minutes = 0 hours = 0 days = 1 months = 1 dt = copy.copy(mydate) return dt.replace(year=years, month=months, day=days, hour=hours, minute=minutes, second=seconds) ###############################################################################
[docs]def compute_datetime_delta(start, end): """Return a dictionary with the accumulated delta in year, month, day, hour, minute and second Usage: .. code-block:: python >>> start = datetime(2001, 1, 1, 00,00,00) >>> end = datetime(2001, 1, 1, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 0, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 0} >>> start = datetime(2001, 1, 1, 00,00,14) >>> end = datetime(2001, 1, 1, 00,00,44) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 0, 'second': 30, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 0} >>> start = datetime(2001, 1, 1, 00,00,44) >>> end = datetime(2001, 1, 1, 00,01,14) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 0, 'second': 30, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 1} >>> start = datetime(2001, 1, 1, 00,00,30) >>> end = datetime(2001, 1, 1, 00,05,30) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 0, 'second': 300, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 5} >>> start = datetime(2001, 1, 1, 00,00,00) >>> end = datetime(2001, 1, 1, 00,01,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 0, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 1} >>> start = datetime(2011,10,31, 00,45,00) >>> end = datetime(2011,10,31, 01,45,00) >>> compute_datetime_delta(start, end) {'hour': 1, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 60} >>> start = datetime(2011,10,31, 00,45,00) >>> end = datetime(2011,10,31, 01,15,00) >>> compute_datetime_delta(start, end) {'hour': 1, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 30} >>> start = datetime(2011,10,31, 00,45,00) >>> end = datetime(2011,10,31, 12,15,00) >>> compute_datetime_delta(start, end) {'hour': 12, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 690} >>> start = datetime(2011,10,31, 00,00,00) >>> end = datetime(2011,10,31, 01,00,00) >>> compute_datetime_delta(start, end) {'hour': 1, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 0} >>> start = datetime(2011,10,31, 00,00,00) >>> end = datetime(2011,11,01, 01,00,00) >>> compute_datetime_delta(start, end) {'hour': 25, 'second': 0, 'max_days': 1, 'year': 0, 'day': 1, 'minute': 0} >>> start = datetime(2011,10,31, 12,00,00) >>> end = datetime(2011,11,01, 06,00,00) >>> compute_datetime_delta(start, end) {'hour': 18, 'second': 0, 'max_days': 0, 'year': 0, 'day': 0, 'minute': 0} >>> start = datetime(2011,11,01, 00,00,00) >>> end = datetime(2011,12,01, 01,00,00) >>> compute_datetime_delta(start, end) {'hour': 721, 'month': 1, 'second': 0, 'max_days': 30, 'year': 0, 'day': 0, 'minute': 0} >>> start = datetime(2011,11,01, 00,00,00) >>> end = datetime(2011,11,05, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'second': 0, 'max_days': 4, 'year': 0, 'day': 4, 'minute': 0} >>> start = datetime(2011,10,06, 00,00,00) >>> end = datetime(2011,11,05, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'second': 0, 'max_days': 30, 'year': 0, 'day': 30, 'minute': 0} >>> start = datetime(2011,12,02, 00,00,00) >>> end = datetime(2012,01,01, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'second': 0, 'max_days': 30, 'year': 1, 'day': 30, 'minute': 0} >>> start = datetime(2011,01,01, 00,00,00) >>> end = datetime(2011,02,01, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 1, 'second': 0, 'max_days': 31, 'year': 0, 'day': 0, 'minute': 0} >>> start = datetime(2011,12,01, 00,00,00) >>> end = datetime(2012,01,01, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 1, 'second': 0, 'max_days': 31, 'year': 1, 'day': 0, 'minute': 0} >>> start = datetime(2011,12,01, 00,00,00) >>> end = datetime(2012,06,01, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 6, 'second': 0, 'max_days': 183, 'year': 1, 'day': 0, 'minute': 0} >>> start = datetime(2011,06,01, 00,00,00) >>> end = datetime(2021,06,01, 00,00,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 120, 'second': 0, 'max_days': 3653, 'year': 10, 'day': 0, 'minute': 0} >>> start = datetime(2011,06,01, 00,00,00) >>> end = datetime(2012,06,01, 12,00,00) >>> compute_datetime_delta(start, end) {'hour': 8796, 'month': 12, 'second': 0, 'max_days': 366, 'year': 1, 'day': 0, 'minute': 0} >>> start = datetime(2011,06,01, 00,00,00) >>> end = datetime(2012,06,01, 12,30,00) >>> compute_datetime_delta(start, end) {'hour': 8796, 'month': 12, 'second': 0, 'max_days': 366, 'year': 1, 'day': 0, 'minute': 527790} >>> start = datetime(2011,06,01, 00,00,00) >>> end = datetime(2012,06,01, 12,00,05) >>> compute_datetime_delta(start, end) {'hour': 8796, 'month': 12, 'second': 31665605, 'max_days': 366, 'year': 1, 'day': 0, 'minute': 0} >>> start = datetime(2011,06,01, 00,00,00) >>> end = datetime(2012,06,01, 00,30,00) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 12, 'second': 0, 'max_days': 366, 'year': 1, 'day': 0, 'minute': 527070} >>> start = datetime(2011,06,01, 00,00,00) >>> end = datetime(2012,06,01, 00,00,05) >>> compute_datetime_delta(start, end) {'hour': 0, 'month': 12, 'second': 31622405, 'max_days': 366, 'year': 1, 'day': 0, 'minute': 0} :return: A dictionary with year, month, day, hour, minute and second as keys() """ comp = {} day_diff = (end - start).days comp["max_days"] = day_diff # Date # Count full years d = end.year - start.year comp["year"] = d # Count full months if start.month == 1 and end.month == 1: comp["month"] = 0 elif start.day == 1 and end.day == 1: d = end.month - start.month if d < 0: d = d + 12 * comp["year"] elif d == 0: d = 12 * comp["year"] comp["month"] = d # Count full days if start.day == 1 and end.day == 1: comp["day"] = 0 else: comp["day"] = day_diff # Time # Hours if start.hour == 0 and end.hour == 0: comp["hour"] = 0 else: d = end.hour - start.hour if d < 0: d = d + 24 + 24 * day_diff else: d = d + 24 * day_diff comp["hour"] = d # Minutes if start.minute == 0 and end.minute == 0: comp["minute"] = 0 else: d = end.minute - start.minute if d != 0: if comp["hour"]: d = d + 60 * comp["hour"] else: d = d + 24 * 60 * day_diff elif d == 0: if comp["hour"]: d = 60 * comp["hour"] else: d = 24 * 60 * day_diff comp["minute"] = d # Seconds if start.second == 0 and end.second == 0: comp["second"] = 0 else: d = end.second - start.second if d != 0: if comp["minute"]: d = d + 60 * comp["minute"] elif comp["hour"]: d = d + 3600 * comp["hour"] else: d = d + 24 * 60 * 60 * day_diff elif d == 0: if comp["minute"]: d = 60 * comp["minute"] elif comp["hour"]: d = 3600 * comp["hour"] else: d = 24 * 60 * 60 * day_diff comp["second"] = d return comp ###############################################################################
[docs]def check_datetime_string(time_string, use_dateutil=True): """Check if a string can be converted into a datetime object and return the object In case datutil is not installed the supported ISO string formats are: - YYYY-mm-dd - YYYY-mm-dd HH:MM:SS - YYYY-mm-ddTHH:MM:SS - YYYY-mm-dd HH:MM:SS.s - YYYY-mm-ddTHH:MM:SS.s Time zones are not supported If dateutil is installed, all string formats of the dateutil module are supported, as well as time zones Time zones are not supported :param time_string: The time string to be checked for conversion :param use_dateutil: Use dateutil if available for datetime string parsing :return: datetime: object or an error message string in case of an error >>> s = "2000-01-01" >>> check_datetime_string(s) datetime.datetime(2000, 1, 1, 0, 0) >>> s = "2000-01-01T10:00:00" >>> check_datetime_string(s) datetime.datetime(2000, 1, 1, 10, 0) >>> s = "2000-01-01 10:00:00" >>> check_datetime_string(s) datetime.datetime(2000, 1, 1, 10, 0) >>> s = "2000-01-01T10:00:00.000001" >>> check_datetime_string(s) datetime.datetime(2000, 1, 1, 10, 0, 0, 1) >>> s = "2000-01-01 10:00:00.000001" >>> check_datetime_string(s) datetime.datetime(2000, 1, 1, 10, 0, 0, 1) # using native implementation, ignoring dateutil >>> s = "2000-01-01" >>> check_datetime_string(s, False) datetime.datetime(2000, 1, 1, 0, 0) >>> s = "2000-01-01T10:00:00" >>> check_datetime_string(s, False) datetime.datetime(2000, 1, 1, 10, 0) >>> s = "2000-01-01 10:00:00" >>> check_datetime_string(s, False) datetime.datetime(2000, 1, 1, 10, 0) >>> s = "2000-01-01T10:00:00.000001" >>> check_datetime_string(s, False) datetime.datetime(2000, 1, 1, 10, 0, 0, 1) >>> s = "2000-01-01 10:00:00.000001" >>> check_datetime_string(s, False) datetime.datetime(2000, 1, 1, 10, 0, 0, 1) """ global has_dateutil if has_dateutil and use_dateutil is True: # First check if there is only a single number, which specifies # relative time. dateutil will interprete a single number as a valid # time string, so we have to catch this case beforehand try: value = int(time_string) return _("Time string seems to specify relative time") except ValueError: pass try: time_object = parser.parse(time_string) except Exception as inst: time_object = str(inst) return time_object # BC is not supported if "bc" in time_string > 0: return _("Dates Before Christ (BC) are not supported") # BC is not supported if "+" in time_string: return _("Time zones are not supported") if ":" in time_string or "T" in time_string: # Check for microseconds if "." in time_string: if "T" in time_string: time_format = "%Y-%m-%dT%H:%M:%S.%f" else: time_format = "%Y-%m-%d %H:%M:%S.%f" else: if "T" in time_string: time_format = "%Y-%m-%dT%H:%M:%S" else: time_format = "%Y-%m-%d %H:%M:%S" else: time_format = "%Y-%m-%d" try: return datetime.strptime(time_string, time_format) except: return _("Unable to parse time string: %s" % time_string) ###############################################################################
[docs]def string_to_datetime(time_string): """Convert a string into a datetime object In case datutil is not installed the supported ISO string formats are: - YYYY-mm-dd - YYYY-mm-dd HH:MM:SS - YYYY-mm-ddTHH:MM:SS - YYYY-mm-dd HH:MM:SS.s - YYYY-mm-ddTHH:MM:SS.s Time zones are not supported If dateutil is installed, all string formats of the dateutil module are supported, as well as time zones :param time_string: The time string to convert :return: datetime object or None in case the string could not be converted """ if not isinstance(time_string, str): return None time_object = check_datetime_string(time_string) if not isinstance(time_object, datetime): msgr = get_tgis_message_interface() msgr.error(str(time_object)) return None return time_object ###############################################################################
[docs]def datetime_to_grass_datetime_string(dt): """Convert a python datetime object into a GRASS datetime string .. code-block:: python >>> import grass.temporal as tgis >>> import dateutil.parser as parser >>> dt = parser.parse("2011-01-01 10:00:00 +01:30") >>> tgis.datetime_to_grass_datetime_string(dt) '01 jan 2011 10:00:00 +0090' >>> dt = parser.parse("2011-01-01 10:00:00 +02:30") >>> tgis.datetime_to_grass_datetime_string(dt) '01 jan 2011 10:00:00 +0150' >>> dt = parser.parse("2011-01-01 10:00:00 +12:00") >>> tgis.datetime_to_grass_datetime_string(dt) '01 jan 2011 10:00:00 +0720' >>> dt = parser.parse("2011-01-01 10:00:00 -01:30") >>> tgis.datetime_to_grass_datetime_string(dt) '01 jan 2011 10:00:00 -0090' """ # GRASS datetime month names month_names = ["", "jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec"] # Check for time zone info in the datetime object if dt.tzinfo is not None: tz = dt.tzinfo.utcoffset(0) if tz.seconds > 86400 / 2: tz = (tz.seconds - 86400) / 60 else: tz = tz.seconds/60 string = "%.2i %s %.2i %.2i:%.2i:%.2i %+.4i" % (dt.day, month_names[dt.month], dt.year, dt.hour, dt.minute, dt.second, tz) else: string = "%.2i %s %.4i %.2i:%.2i:%.2i" % (dt.day, month_names[ dt.month], dt.year, dt.hour, dt.minute, dt.second) return string ###############################################################################
suffix_units = {"years": "%Y", "year": "%Y", "months": "%Y_%m", "month": "%Y_%m", "weeks": "%Y_%m_%d", "week": "%Y_%m_%d", "days": "%Y_%m_%d", "day": "%Y_%m_%d", "hours": "%Y_%m_%d_%H", "hour": "%Y_%m_%d_%H", "minutes": "%Y_%m_%d_%H_%M", "minute": "%Y_%m_%d_%H_%M"}
[docs]def create_suffix_from_datetime(start_time, granularity): """Create a datetime string based on a datetime object and a provided granularity that can be used as suffix for map names. dateteime=2001-01-01 00:00:00, granularity="1 month" returns "2001_01" :param start_time: The datetime object :param granularity: The granularity for example "1 month" or "100 seconds" :return: A string """ global suffix_units return start_time.strftime(suffix_units[granularity.split(' ')[1]])
[docs]def create_time_suffix(mapp, end=False): """Create a datetime string based on a map datetime object :param mapp: a temporal map dataset :param end: True if you want add also end time to the suffix """ start = mapp.temporal_extent.get_start_time() sstring = start.isoformat().replace(':', '_').replace('-', '_') if end: end = mapp.temporal_extent.get_end_time() estring = end.isoformat().replace(':', '_').replace('-', '_') return "{st}_{en}".format(st=sstring, en=estring) return sstring
[docs]def create_numeric_suffic(base, count, zeros): """Create a string based on count and number of zeros decided by zeros :param base: the basename for new map :param count: a number :param zeros: a string containing the expected number, coming from suffix option """ spli = zeros.split('%') if len(spli) == 2: suff = spli[1] if suff.isdigit(): if int(suff[0]) == 0: zero = suff else: zero = "0{nu}".format(nu=suff) else: zero = '05' else: zero = '05' s = '{ba}_{i:' + zero + 'd}' return s.format(ba=base, i=count)
if __name__ == "__main__": import doctest doctest.testmod()

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