Python - Date, Time

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http://www.tutorialspoint.com/python/python_date_time.htm

https://docs.python.org/2/library/datetime.html

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TimeZone and Local time

import os, time

print(time.ctime())

#FRED : doesn't work in Windows, only UNIX/Linux
# Set local time zone to NYC
os.environ['TZ']='America/New_York'
time.tzset()
print time.strftime('%X %x %Z')

os.environ['TZ'] = 'EST+05EDT,M4.1.0,M10.5.0'
time.tzset()
print time.strftime('%X %x %Z')

t=time.localtime() # string
print(time.ctime())

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from datetime import date
from datetime import time
from datetime import datetime

def main():
  ## DATE OBJECTS
  # Get today's date from the simple today() method from the date class
  today = date.today()
  print "Today's date is ", today
  
  # print out the date's individual components
  print "Date Components: ", today.day, today.month, today.year
  
  # retrieve today's weekday (0=Monday, 6=Sunday)
  print "Today's Weekday #: ", today.weekday()
  
  ## DATETIME OBJECTS
  # Get today's date from the datetime class
  today = datetime.now()
  print  "The current date and time is ", today
  
  # Get the current time
  t = datetime.time(datetime.now())
  print "The current time is ", t
  
  # weekday returns 0 (monday) through 6 (sunday)
  wd = date.weekday(today)  
  # Days start at 0 for Monday 
  days = ["monday","tuesday","wednesday","thursday","friday","saturday","sunday"]
  print "Today is day number %d" % wd
  print "Which is a " + days[wd]
  
  
if __name__ == "__main__":
  main();
 

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Formatting

http://www.tutorialspoint.com/python/time_strftime.htm

from datetime import datetime

def main():
  # Times and dates can be formatted using a set of predefined string
  # control codes 
  now = datetime.now() # get the current date and time
  
  #### Date Formatting ####
  
  # %y/%Y - Year, %a/%A - weekday, %b/%B - month, %d - day of month
  print now.strftime("%Y") # full year with century
  print now.strftime("%a, %d %B, %y") # abbreviated day, num, full month, abbreviated year
  
  # %c - locale's date and time, %x - locale's date, %X - locale's time
  print now.strftime("%c")
  print now.strftime("%x")
  print now.strftime("%X")
  
  #### Time Formatting ####
  
  # %I/%H - 12/24 Hour, %M - minute, %S - second, %p - locale's AM/PM
  print now.strftime("%I:%M:%S %p") # 12-Hour:Minute:Second:AM
  print now.strftime("%H:%M") # 24-Hour:Minute

  ## Fred's preference
  print now.strftime("FRED date_time format: %Y%m%d_%H%M%S")

if __name__ == "__main__":
  main();

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Diff, counting date, time

from datetime import date
from datetime import time
from datetime import datetime
from datetime import timedelta

# construct a basic timedelta and print it
print timedelta(days=365, hours=5, minutes=1)

# print today's date
print "today is: " + str(datetime.now())

# print today's date one year from now
print "one year from now it will be: " + str(datetime.now() + timedelta(days=365))

# create a timedelta that uses more than one argument
print "in two weeks and 3 days it will be: " + str(datetime.now() + timedelta(weeks=2, days=3))

# calculate the date 1 week ago, formatted as a string
t = datetime.now() - timedelta(weeks=1)
s = t.strftime("%A %B %d, %Y")
print "one week ago it was " + s

### How many days until April Fools' Day?

today = date.today()  # get today's date
afd = date(today.year, 4, 1)  # get April Fool's for the same year
# use date comparison to see if April Fool's has already gone for this year
# if it has, use the replace() function to get the date for next year
if afd < today:
  print "April Fool's day already went by %d days ago" % ((today-afd).days)
  afd = afd.replace(year=today.year + 1)  # if so, get the date for next year

# Now calculate the amount of time until April Fool's Day  
time_to_afd = abs(afd - today)
print time_to_afd.days, "days until next April Fools' Day!"

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import calendar

# create a plain text calendar
c = calendar.TextCalendar(calendar.SUNDAY)
str = c.formatmonth(2015, 1, 0, 0)
print str

# create an HTML formatted calendar
hc = calendar.HTMLCalendar(calendar.SUNDAY)
str = hc.formatmonth(2015, 1)
print str

# loop over the days of a month
# zeroes mean that the day of the week is in an overlapping month
for i in c.itermonthdays(2015, 8):
  print i

# The Calendar module provides useful utilities for the given locale,
# such as the names of days and months in both full and abbreviated forms
for name in calendar.month_name:
  print name

for day in calendar.day_name:
  print day

# Calculate days based on a rule: For example, consider
# a team meeting on the first Friday of every month.
# To figure out what days that would be for each month,
# we can use this script:
for m in range(1,13):
  # returns an array of weeks that represent the month
  cal = calendar.monthcalendar(2015, m)
  # The first Friday has to be within the first two weeks
  weekone = cal[0]
  weektwo = cal[1]
   
  if weekone[calendar.FRIDAY] != 0:
    meetday = weekone[calendar.FRIDAY]
  else:
    # if the first friday isn't in the first week, it must be in the second
    meetday = weektwo[calendar.FRIDAY]
      
  print "%10s %2d" % (calendar.month_name[m], meetday)

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