I am trying to prepare a plot on the UK national grid. This is a transverse mercator projection centred on the UK with a false origin offset from the projection origin (lat_0, lon_0).
The Basemap coordinate system origin (0 Easting and Northing) always seems to be set in the lower-left corner of the plot. The plot I need includes data either side of the origin so I need the origin within the plot area.
Is there a general way of setting the origin somewhere other than the lower-left corner?
I can either get basemap to plot the correct data region, in which case the origin is in the wrong place or I can fool Basemap by adjusting the axes bounds later. However, if I do this some of the coastline isn't plotted because Basemap decides it isn't on the map.
Cheers,
Stephen.
I've just had to deal with a similar problem, you need to use the
basemap.shiftgrid() method to shift the co-ordinate grid accordingly.
Cheers
Adam
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On 10/10/2007, Pascoe, S (Stephen) <S.Pascoe@...959...> wrote:
Is there a general way of setting the origin somewhere other than the lower-left corner?
Pascoe, S (Stephen) wrote:
I am trying to prepare a plot on the UK national grid. This is a transverse mercator projection centred on the UK with a false origin offset from the projection origin (lat_0, lon_0).
The Basemap coordinate system origin (0 Easting and Northing) always seems to be set in the lower-left corner of the plot. The plot I need includes data either side of the origin so I need the origin within the plot area.
Is there a general way of setting the origin somewhere other than the lower-left corner?
I can either get basemap to plot the correct data region, in which case the origin is in the wrong place or I can fool Basemap by adjusting the axes bounds later. However, if I do this some of the coastline isn't plotted because Basemap decides it isn't on the map.
Cheers,
Stephen.
Stephen: There's no way to change the coordinate system Basemap uses. To get you data to plot in the correct place, just add an offset
xoffset, yoffset = map(lon_0, lat_0)
to the UK national grid coordinates of the data you are plotting.
HTH,
-Jeff
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