IGRAUpperAir returns wrong release time in the header due to excess padding of string in _ctime function

[awalkermag]

The _ctime function in igra2.py is supposed to work for both MMMSS and HHMM formats, but is always padding the input string to 5 characters, which causes the hour and minute substrings of the HHMM format to be wrong. This can be seen by running the following copy of the _ctime code, with some print statements added.:

# Copy of _ctime function from igra2.py, with print statements added
def _ctime(strformat='MMMSS'):
    """Return a function converting a string from MMMSS or HHMM to seconds."""
    def _ctime_strformat(val):
        print('val',val)
        time = val.strip().zfill(5)
        print('time',time)
        if int(time) < 0 or int(time) == 9999:
            return np.nan
        else:
            if strformat == 'MMMSS':
                minutes = int(time[0:3])
                seconds = int(time[3:5])
                time_seconds = minutes * 60 + seconds
            elif strformat == 'HHMM':
                hours = int(time[0:2])
                minutes = int(time[2:4])
                print('hours minutes', hours,minutes)
                time_seconds = hours * 3600 + minutes * 60
            else:
                sys.exit('Unrecognized time format')

        return time_seconds
    return _ctime_strformat

# Call the function and print the result
func = _ctime(strformat='HHMM')
print(func('1142'))

The result is this:

val 1142
time 01142
hours minutes 1 14
4440

You can see the hours and minutes are not being correctly extracted from the input, so the resulting number of seconds computed is wrong. To fix this, the 5-char padding should be applied only when the format is MMMSS, and 4-char padding should be applied when the format is HHMM.