import pandas as pd
from pandas import Series, DataFrame
from itertools import islice
import datetime
import time
import pytz
s0 = "Open Data"
len(s0), s0[::-1], s0[2]
# something simple to start
datetime.datetime.now().month
# tests whether you know the basics of datetime, what fromtimestap does, and notion of timedelta
dt = datetime.datetime.fromtimestamp(86400) - datetime.datetime.fromtimestamp(0)
dt.total_seconds(), dt.days
pytz.timezone('US/Pacific').localize(datetime.datetime.fromtimestamp(0)).astimezone(pytz.utc)
def triangle():
f = 0
n = 1
while True:
f += n
yield f
n += 1
# hint list(islice([0,1,2,3,4], 2)) is [0,1]
f = triangle()
list(islice(f,4))
s = Series(arange(3), index = ['a','b','c'])
s['b']
s.order()[::-1][0]
df = DataFrame([{'name':'UC Berkeley', 'city':'Berkeley', 'state':'CA'}, {'name':'MIT', 'city':'Cambridge', 'state':'MA'},
{'name':'Stanford', 'city':'Stanford', 'state':'CA'}, {'name':'Harvard', 'city':'Cambridge', 'state':'MA'}])
sum(df[df.state == 'CA'].name.str.len())
# put into words what we're trying to calculate and give the answer