Can't get the real time difference between two times in hours-CodePudding

When I run this code it works fine, but it gives me the wrong time difference

import datetime

start_time = "02:30 PM"
end_time = "01:30 AM"

firstTime = datetime.datetime.strptime(start_time , "%I:%M %p")
print(f"Datetime Start Time is {firstTime}")

endTime = datetime.datetime.strptime(end_time , "%I:%M %p")
print(f"Datetime End Time Is {endTime}")

deltaTime = firstTime-endTime

print(f"Time Difference is {deltaTime.total_seconds()/(60*60)} hours")

When I check the time difference in google it says 11 hours, but this code returns 13 hours why is that?

CodePudding user response：

The code is correct.

It will calculate form the same day. Since you have not mentined the start day.

Datetime Start Time is 1900-01-01 14:30:00
Datetime End Time Is 1900-01-01 01:30:00
Time Difference is 13.0 hours

So, when you take the difference between 01:30 and 14:30 on the same day that is 1900-01-01 the difference will be 13 hours as 01:30 comes before 14:30

CodePudding user response：

I think it might have to do with your subtraction deltaTime = firstTime-endTime

Basically if count from the endTime to firstTime it's doing a 14:30 - 1:30 instead of doing a 1:30 - 14:30

I suggest you change the order of the math count and then format the answer because the value of deltaTime will be -1 day, 11:00:00

CodePudding user response：

I think you can handle that by adding a simple (if.. else) statement with datetime.timedetla to shift the difference by one day in case your end_time falls on the next day.

deltaTime = endTime - firstTime

timeDiff = deltaTime   timedelta(days=1) if deltaTime.days < 0 else deltaTime

Output :

print(f"Time difference is {timeDiff.total_seconds()/3600} hours")
#Time difference is 11.0 hours