Remove clipping from lonlat2cell #77
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When using the current implementation of `lonlat2cell` with cellsize < 1, the clipping leads to very large cells. For example, with `cellsize=0.5` all points with lat>0 and lon>0 will be mapped to the same cell, because in this case `(lat+90)/cellsize = (lat+90)*2 > 180` and similarly `(lon+180)/cellsize = (lon+180)*2 > 360`. When using cellsize >= 1, clipping is only necessary if latitude and longitude are not in (-90, 90) and (-180, 180), respectively, but this is already enforced in the BasicGrid init, so it shouldn't be necessary here.
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When using the current implementation of
lonlat2cellwith cellsize < 1, the clipping messes up cells, because everything in the upper right corner of the map is mapped to the same cell.For example, with
cellsize=0.5all points with lat>0 and lon>0, we will gety = (lat+90)/cellsize = (lat+90)*2 > 180and similarlyx = (lon+180)/cellsize = (lon+180)*2 > 360, and due to clipping they all will be assignedy = 180andx = 360.When using cellsize >= 1, clipping is only necessary if latitude and longitude are not in (-90, 90) and (-180, 180), respectively, but this is already enforced in the BasicGrid init, so it shouldn't be necessary here.
Therefore I think it's safe to remove the clipping here.