Unexpected Nans in get_observer_look_no_tle

[Nina]

Code Sample, a minimal, complete, and verifiable piece of code

import numpy as np
from pyorbital.orbital import get_observer_look as get_observer_look_no_tle
sat_alt = 850.0  # km  TIROS-N OSCAR
lons = np.linspace(-180, 180, num=1000)
lats = np.linspace(-90, 90, num=1000)
times = np.datetime64('2015-02-25T04:30')
sat_azi, sat_elev = get_observer_look_no_tle(
    lons,
    lats,
    sat_alt,  # approximate satellite altitude
    times[np.newaxis],
    lons, lats, 0)

if np.isnan(sat_elev).any():
    raise ValueError

Problem description

The angle of sat_elev is sometimes calculated as NaNs instead of being ~90.

Expected Output

No error.

Actual Result, Traceback if applicable

ValueError

Versions of Python, package at hand and relevant dependencies

Thank you for reporting an issue !

[David Hoese]

This may be a duplicate of #68