python - trouble selecting a period of dates in Pandas with < and > -

a simple question perhaps, it's first time working pandas , i'm having trouble slicing dataframes smaller ones based on dates.

so, have dataframe (named firstreadin) looks (and thousands more rows):

        date               numbers  megaball 0 1999-01-12     [5, 7, 9, 20, 46]         2 1 1999-01-08   [5, 21, 23, 26, 37]         3 2 1999-01-05   [4, 31, 32, 34, 43]        19 3 1999-01-01  [11, 19, 28, 43, 48]         5 4 1998-12-29     [3, 5, 7, 28, 35]        10 

and want slice them couple periods given specific date dividers, , while i'm having no trouble specifying first , last periods, can't seem specify middle periods:

#firsttime , secondtime date separators firsttime = datetime.datetime.strptime('1/13/99', '%m/%d/%y') secondtime = datetime.datetime.strptime('5/15/02', '%m/%d/%y')  firstperiod = firstreadin[firstreadin.date < firsttime].reset_index(drop=true) thirdperiod = firstreadin[firstreadin.date > secondtime].reset_index(drop=true) 

i can't secondperiod! (the 1 between firsttime , secondtime). i've tried this:

secondperiod = firstreadin[firstreadin.date >= firsttime , firstreadin.date < secondtime]  

but gives me valueerror: truth value of series ambiguous. use a.empty, a.bool(), a.item(), a.any() or a.all().

what's going on , how should solve it? thanks!

you can use numpy.logical_and: numpy.logical_and(a, b)

    secondperiod = firstreadin[numpy.logical_and(firstreadin.date >= firsttime, firstreadin.date < secondtime)] 

i hope can you!