datetimeFunctions.py

from netCDF4 import Dataset, date2num, num2date
import os
from datetime import datetime, timedelta
import calendar

__author__ = 'Trond Kristiansen'
__email__ = 'me@trondkristiansen.com'
__created__ = datetime(2015, 8, 11)
__modified__ = datetime(2018, 4, 25)
__version__ = "1.5"
__status__ = "Development, modified on 19.04.2018 by A.Barthel, " \
             "refactored 25.04.2018 by Trond Kristiansen"


# Methods for returning list of months and days for the given time-step.

def createlistofmonths(confM2R, currentyear):

    if currentyear == confM2R.startdate.year:
        IDS = [confM2R.startdate.month + m for m in range(13 - confM2R.startdate.month)]
        # months from start month to end of first year

    elif currentyear == confM2R.enddate.year:
        IDS = [1 + m for m in range(int(confM2R.enddate.month))]
        # months from first month to last month of last year

    elif confM2R.startdate.year < currentyear < confM2R.enddate.year:
        # months from first month to last month of last year
        IDS = [1 + m for m in range(12)]

    if confM2R.startdate.year == confM2R.enddate.year:
        # months from first month to last month of last year
        IDS = [confM2R.startdate.month + m for m in range(confM2R.enddate.month - confM2R.startdate.month + 1)]

    if confM2R.isclimatology:
        IDS = [i + 1 for i in range(12)]

    if not IDS:
        print("Unable to generate IDS for time looping: main.py -> func createIDS")
        sys.exit()

    return IDS


def createlistofdays(confM2R, year, month):
    days = []
    if confM2R.timefrequencyofinputdata == 'day':
        daystep = 7
        if daystep > 1:
            print("WARNING!")
            print("----------------------------------------------------------------------")
            print("You are only using every {} days of input data! (model2roms.py)".format(daystep))
            print("----------------------------------------------------------------------")

        # Regulary we want all days in each month                
        ndays = int(calendar.monthrange(year, month)[1])
        days = [d + 1 for d in range(0, ndays, daystep)]

        # Exceptions:
        # We start in the first month after day one
        if (month == confM2R.startdate.month and year == confM2R.startdate.year and confM2R.startdate.day > 1):
            days = [i for i in range(confM2R.startdate.day, ndays, daystep)]

        # We finish in the last month before last day of month
        if (month == confM2R.enddate.month and year == confM2R.enddate.year):
            days = [i + 1 for i in range(0, confM2R.enddate.day, daystep)]

        # We start and end on different days in the same month         
        if (confM2R.startdate.month == confM2R.enddate.month and confM2R.startdate.year == confM2R.enddate.year):
            days = [i for i in range(confM2R.startdate.day, confM2R.enddate.day, daystep)]
    
    if confM2R.timefrequencyofinputdata == '5days':
        
        for dd in confM2R.timeobject[:]:
            dd_date = num2date(dd,units=confM2R.timeobject.units, calendar=confM2R.timeobject.calendar)

            if dd_date.year==year and dd_date.month==month:
                days.append(dd_date.day)
                print(dd_date)

        return days

    if confM2R.timefrequencyofinputdata == 'month':
        days = [15]

    return days