Is there a Python function to determine which quarter of the year a date is in?

Question

Sure I could write this myself, but before I go reinventing the wheel is there a function that already does this?

Answer 1

IF you are already using pandas, it's quite simple.

import datetime as dt
import pandas as pd

quarter = pd.Timestamp(dt.date(2016, 2, 29)).quarter
assert quarter == 1

If you have a date column in a dataframe, you can easily create a new quarter column:

df['quarter'] = df['date'].dt.quarter

Answer 2

For those, who are looking for financial year quarter data, using pandas,

import datetime
import pandas as pd
today_date = datetime.date.today()
quarter = pd.PeriodIndex(today_date, freq='Q-MAR').strftime('Q%q')

reference: pandas period index

Answer 3

hmmm so calculations can go wrong, here is a better version (just for the sake of it)

first, second, third, fourth=1,2,3,4# you can make strings if you wish :)

quarterMap = {}
quarterMap.update(dict(zip((1,2,3),(first,)*3)))
quarterMap.update(dict(zip((4,5,6),(second,)*3)))
quarterMap.update(dict(zip((7,8,9),(third,)*3)))
quarterMap.update(dict(zip((10,11,12),(fourth,)*3)))

print quarterMap[6]

Answer 4

This method works for any mapping:

month2quarter = {
        1:1,2:1,3:1,
        4:2,5:2,6:2,
        7:3,8:3,9:3,
        10:4,11:4,12:4,
    }.get

We have just generated a function int->int

month2quarter(9) # returns 3

This method is also fool-proof

month2quarter(-1) # returns None
month2quarter('July') # returns None

Answer 5

for m in range(1, 13):
  print ((m*3)//10)

Answer 6

I would suggest another arguably cleaner solution. If X is a datetime.datetime.now() instance, then the quarter is:

import math
Q=math.ceil(X.month/3.)

ceil has to be imported from math module as it can't be accessed directly.