I have to convert a MATLAB's datenum to Python's datetime.
The following code is as below:
import datetime
matlab_datenum = 63650571169.50261
python_datetime = datetime.date.fromordinal(int(matlab_datenum)) + \
datetime.timedelta(days=matlab_datenum%1) - datetime.timedelta(days=366)
print(matlab_datenum)
The above code generates this error:
OverflowError: Python int too large to convert to C long
How, can I resolve this problem?
Your datenum is in seconds from the matlab epoch. To convert to a datetime you need to offset that number of seconds to a datetime that python understands. This function uses the Unix epoch as that reference.
Code:
import datetime as dt
# define some constants
epoch = dt.datetime(1970, 1, 1)
matlab_to_epoch_days = 719529 # days from 1-1-0000 to 1-1-1970
matlab_to_epoch_seconds = matlab_to_epoch_days * 24 * 60 * 60
def matlab_to_datetime(matlab_date_num_seconds):
# get number of seconds from epoch
from_epoch = matlab_date_num_seconds - matlab_to_epoch_seconds
# convert to python datetime
return epoch + dt.timedelta(seconds=from_epoch)
Test Code:
print(matlab_to_datetime(63650571169.50261))
Results:
2017-01-01 10:12:49.502609
63650571169.50261this number seems to big to be a MATLAB datenum first of all, MATLAB datenums are number of days from January 0, 0000, this number is equivalent to 174385126 years. Is this the time when aliens are going to make contact ? The overflow issue could be related to this