[latlim,lonlim]
= geoquadline(lat,lon) returns
the limits of the tightest possible geographic quadrangle that bounds
a line connecting vertices with geographic coordinates specified by lat and lon.

Latitudes along a line, specified as a vector representing an
ordered sequences of vertices, in units of degrees. The line may be
broken into multiple parts, delimited by values of NaN.

Longitudes along a line, specified as a vector representing
an ordered sequences of vertices, in units of degrees. The line may
be broken into multiple parts, delimited by values of NaN.

Latitude limits of a geographic quadrangle, returned as a 1-by-2
vector of the form [southern_limit northern_limit],
in units of degrees. The elements are in ascending order, and both
lie in the closed interval [-90 90].

Longitude limits of a geographic quadrangle, returned as a 1-by-2
vector of the form [western_limit eastern_limit],
in units of degrees. The limits are wrapped to the interval [-180
180]. They are not necessarily in numerical ascending order.