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pythoncartopy

Reproducing extent of cartopy plots with orthographic projection

I am generating set of different maps and I would like them to all have the same axis limits. However, I am having a hard time figuring out how to set the extent.

import matplotlib.pyplot as plt
import cartopy.crs as ccrs

lon = -90
lat = 90
proj =  ccrs.Orthographic

projection = proj(lon, lat)
fig = plt.figure()
ax = fig.add_subplot(1, 1, 1, projection = projection)

transform = ccrs.Geodetic()

lat0 = 50
lon0 = 50

for x in range(-5,6):
    plt.plot(lon0 + x, lat0, 'bo', transform = transform)
    plt.plot(lon0, lat0 + x, 'bo', transform = transform)

mwe1

I want to be able to extract the extent of the "map" and then apply it to other maps that will autoscale differently. However, even when I try to extract the extent and reapply it to the same figure, it fails.

a = ax.get_extent(crs = proj())
#a = (2769836.95350539, 3487499.8040009444, 4467034.2547478145, 5254224.255689873)
ax.set_extent(a, crs = proj())

mwe2

Solution

  • Kind of obvious once I realized it, but the lon and lat of projection need to be specified in the extent description.

    a = ax.get_extent(crs = proj(lon, lat))
ax.set_extent(a, crs = proj(lon, lat))

    mwe_fixed