Python Forum

Hi there

From my understanding, you can use the

import datetime

module to subtract two different datetimes. But when I try to execute this, my code throws the error: TypeError: unsupported operand type(s) for -: 'datetime.datetime' and 'tuple'. Below is my code. Any reason why this isn't working? Everything is formatted the same.

flightDate = datetime.datetime(flight_year, flight_month, flight_day, flight_hour, 0, 0) 
GFSDate = int(time.strftime("%Y%m%d"))
GFSDate = str(GFSDate)
GFSDateTime = datetime.datetime(int(GFSDate[:4]),int(GFSDate[4:6]),int(GFSDate[6:]),GFSTime, 0, 0)
def findGFSTimeIndex(predictionDateTime, GFSDateTime):
    diff = predictionDateTime - GFSDateTime
    return int(np.round((diff.total_seconds()/3600)/3))

But I am actually using it with these parameters later on, which is where it is getting snagged:

timeIndex = GFSReader.findGFSTimeIndex(flightDate, gfsDate)

Which then gives the error:

TypeError: unsupported operand type(s) for -: 'datetime.datetime' and 'tuple'

I'm confused where this is coming from because everywhere I have looked, it says you can subtract datetime.datetime values. Any suggestions? Thanks!

Because you're passing gfsDate, not GFSDatetime. I'm assuming gfsDate came from the time module, which uses tuples.