Read time from excel sheet using xlrd, in time format and not in float

Question

I am trying to read some data from a excel file. One of the columns has time values in the format HH:MM:SS. Xlrd reads this time and converts it into float. I have another time values in my python file which I want to compare with the excel-imported time values. I am not able to do that as long as one of them is a "time" and the other is a "float". Any suggestions?

This is how my excel file looks like -

Time    L_6_1   PW_6_1  Tc_6_1  Te_6_1

0:00:00 10000   500 290 270
1:00:00 10000   600 290 270
2:00:00 10000   700 290 270
3:00:00 10000   800 290 270
4:00:00 10000   900 290 270

And this is how I am reading this data -

wb=xlrd.open_workbook('datasheet.xls')
sh = wb.sheet_by_index(0)
timerange=sh.col_values(0)
print timerange

This is the output with float values for time -

[u'Time', 0.0, 0.041666666666666664, 0.083333333333333301, 0.125, 0.166666666666
66699, 0.20833333333333301, 0.25, 0.29166666666666702, 0.33333333333333298, 0.37
5, 0.41666666666666702, 0.45833333333333298, 0.5, 0.54166666666666696, 0.5833333
3333333304, 0.625, 0.66666666666666696, 0.70833333333333304, 0.75, 0.79166666666
666696, 0.83333333333333304, 0.875, 0.91666666666666696, 0.95833333333333304]

Answer 1

The xlrd library has a built-in, xldate_as_tuple() function for getting you most of the way there:

import xlrd
from datetime import time
wb=xlrd.open_workbook('datasheet.xls')

date_values = xlrd.xldate_as_tuple(cell_with_excel_time, wb.datemode)  

# date_values is now a tuple with the values: (year, month, day, hour, minute, seconds),
# so you just need to pass the last 3 to the time() function.
time_value = time(*date_values[3:])

Answer 2

Excel stores times as fractions of a day. You can convert this to a Python time as follows:

from datetime import time

x = excel_time # a float
x = int(x * 24 * 3600) # convert to number of seconds
my_time = time(x//3600, (x%3600)//60, x%60) # hours, minutes, seconds

If you need more precision, you can get it by converting to milliseconds or microseconds and creating a time that way.

Answer 3

    def convert_excel_time(t, hour24=True):
        if t > 1:
            t = t%1
        seconds = round(t*86400)
        minutes, seconds = divmod(seconds, 60)
        hours, minutes = divmod(minutes, 60)
        if hour24:
            if hours > 12:
                hours -= 12
                return "%d:%d:%d PM" % (hours, minutes, seconds)
            else:
                return "%d:%d:%d AM" % (hours, minutes, seconds)
        return "%d:%d:%d" % (hours, minutes, seconds)


print convert_excel_time(0.400983796)
print convert_excel_time(0.900983796, hour24=False)
print convert_excel_time(0.4006944444444)
print convert_excel_time(1.4006944444444)