Negative Latitude Value
eliascotto opened this issue · comments
Elia Scotto commented
Hi,
when I create a map with a large set of cities, the library rase an errore like this one
Traceback (most recent call last):
File "/xxx/pyxxx.py", line 71, in <module>
image = m.render(zoom=1)
File "/usr/local/lib/python2.7/dist-packages/staticmap/staticmap.py", line 268, in render
extent = self.determine_extent(zoom=self.zoom)
File "/usr/local/lib/python2.7/dist-packages/staticmap/staticmap.py", line 304, in determine_extent
y = _lat_to_y(e[1], zoom)
File "/usr/local/lib/python2.7/dist-packages/staticmap/staticmap.py", line 141, in _lat_to_y
return (1 - log(tan(lat * pi / 180) + 1 / cos(lat * pi / 180)) / pi) / 2 * pow(2, zoom)
ValueError: math domain error
So, the math domain error
is probably related to the log
function, that with negative number is mathematically undefined.
Christoph Lingg commented
tan
is not defined for latitude = ±90
. it seems you want to draw a city exactly on the north pole or south pole. that's actually not possible with the usual (=mercator) projection.
Without knowing your data that's my best guess. Can you check your data for suspicious latitude values?