Feature #2909
convert GTime to python datetime object and back
| Status: | Closed | Start date: | 06/25/2019 | |
|---|---|---|---|---|
| Priority: | Normal | Due date: | ||
| Assigned To: |  Kelley-Hoskins Nathan | % Done: | 100% | |
| Category: | - | |||
| Target version: | 1.7.0 | |||
| Duration: |
Description
I wrote a python function in my code to convert a GTime object to a python datetime object.
def gtime2datetime( gt ) :
"""Convert GTime object to a python datetime object
**Args:**
gt : GTime object
**Returns:**
datetime.datetime object
"""
# gt.utc() can spit out seconds=60, which can do wonky
# things to a simple datetime.datetime object (which
# requires seconds to be 0-59 inclusive). This code
# seems to get around this problem, from:
# http://stackoverflow.com/a/21029510/2500768
f = '%Y-%m-%dT%H:%M:%S %Z'
utc_time_tuple = time.strptime( gt.utc() + ' UTC', f )
dt = datetime.datetime(1970,1,1) + datetime.timedelta( seconds= calendar.timegm( utc_time_tuple ) )
return dt
I’d like to add this, as well as the reverse operation datetime2gtime(), to the GTime class. I think since a datetime object doesn’t really exist in the c++ world, these functions will probably just be added to the GTime.i swig interface. In the end their usage would look something like:
t = gammalib.GTime() d = t.datetime() # returns a datetime object
d = datetime.datetime() # and then either: t = gammalib.GTime(d) # or t = gammalib.GTime().datetime(d)
Recurrence
No recurrence.
History
#1
Updated by Kelley-Hoskins Nathan almost 5 years ago
- Assigned To set to Kelley-Hoskins Nathan
#2
Updated by Kelley-Hoskins Nathan almost 5 years ago
- Status changed from New to Pull request
#3
Updated by Kelley-Hoskins Nathan almost 5 years ago
GTime.utc() doesn’t return fractional seconds (YYYY-MM-DDThh:mm:ss), so I had to edit GTime.cpp to YYYY-MM-DDThh:mm:ss.ssssss in order for the converter to work properly.
#4
Updated by Kelley-Hoskins Nathan almost 5 years ago
- Status changed from Pull request to In Progress
#5
Updated by Kelley-Hoskins Nathan almost 5 years ago
- Status changed from In Progress to Pull request
Changing the format of the returned utc() string may affect other code, so I added a variable 'precision’ argument that defaults to zero.
#6
Updated by Kelley-Hoskins Nathan almost 5 years ago
- % Done changed from 0 to 80
#7
Updated by Knödlseder Jürgen almost 5 years ago
- Target version set to 1.7.0
- % Done changed from 80 to 100
I needed to adapt the code so that it still works on Python version earlier than 2.6. Here is how the code now looks like:
%pythoncode %{
def datetime(self, *args):
"""
Convert the GTime data into a datetime.datetime object.
Usage 1:
import gammalib
t = gammalib.GTime()
d = t.datetime() # returns a datetime.datetime object
Usage 2:
import gammalib, datetime
d = datetime.datetime.now()
t = gammalib.GTime()
t.datetime(d) # set the GTime to the datetime's time.
Parameters
----------
args[0] : datetime.datetime object, if present, sets gtime to
this time.
Returns
-------
datetime : datetime.datetime object if no input argument,
otherwise returns nothing
"""
# Import modules
#import time, datetime, calendar
import time, datetime
# If no datetime argument then return a datetime object
if len(args) == 0:
#f = '%Y-%m-%dT%H:%M:%S.%f %Z'
#d = datetime.datetime.strptime(self.utc(6) + ' UTC', f)
(t, msecs) = self.utc(6).strip().split('.')
d = datetime.datetime(*(time.strptime(t, '%Y-%m-%dT%H:%M:%S')[0:6]))
d = d.replace(microsecond=int(msecs))
return d
# ... otherwise, if an argument is given, set the gtime to the datetime
# argument
elif len(args) == 1:
dt = args[0]
if type(dt) is datetime.datetime:
#s = dt.strftime('%Y-%m-%dT%H:%M:%S.%f')
s = dt.strftime('%Y-%m-%dT%H:%M:%S')+'.%6.6d' % (dt.microsecond)
self.utc(s)
else:
msg = 'Argument must be a datetime.datetime object, is '
msg += 'currently ' + str(dt.__class__)
raise TypeError(msg)
# ... otherwise raise an exception
else:
msg = 'GTime.datetime() needs 0 or 1 arguments. It was given '
msg += '%d.' % len(args)
raise ValueError(msg)
# Return
return
%}
Everything is merged into
devel.#8
Updated by Knödlseder Jürgen almost 5 years ago
- Status changed from Pull request to Closed