Possibly an issue with get_lonlats() for robinson projection #232
Description
Code Sample, a minimal, complete, and verifiable piece of code
import matplotlib.pyplot as plt
from pyresample import load_area
import copy
import matplotlib
# Create colormap with high values red
my_cmap = copy.copy(matplotlib.cm.BrBG)
my_cmap.set_over('red', alpha=1)
# Create axis
fig = plt.figure()
ax, ax2 = fig.subplots(nrows=2)
# Plot ortho longitudes
area_def = load_area('areas.yaml', 'ortho')
lon, lat = area_def.get_lonlats()
ax.imshow(lon, vmin=-180, vmax=180, cmap=my_cmap)
#Plot robinson longitudes
area_def = load_area('areas.yaml', 'robinson')
lon, lat = area_def.get_lonlats()
ax2.imshow(lon, vmin=-180, vmax=180, cmap=my_cmap)
# Save or show
plt.savefig('test_robinson.png')
plt.show()ortho:
description: Ortho globe
projection:
proj: ortho
lon_0: 40.
lat_0: -40.
a: 6370997.0
shape:
height: 480
width: 640
area_extent:
lower_left_xy: [-10000000, -10000000]
upper_right_xy: [10000000, 10000000]
robinson:
description: robinson
projection:
proj: robin
lat_0: 0.0
lon_0: 0.0
ellps: WGS84
shape:
height: 480
width: 640
area_extent:
lower_left_xy: [-17900000.0, -8800000.0]
upper_right_xy: [17900000.0, 8800000.0]Problem description
I am trying to resample and plot data on a Robinson projection.
However when plotting I get data also in the 4 corners. I have found away around it
and was thinking of adding an example to the docs.
But when using the ortho projection there is no problem with data in the corners.
Longitudes retrieved by get_lonlats() are for the ortho projection very large 10^30
in the corners outside the globe. However for the robinson projection they are not.
Expected Output
I would have expected longitude outside the globe to be very large or nan or nodata
for both the robinson and ortho projection. In the attached picture I expected red color outside the globe.
Actual Result, Traceback if applicable
Versions of Python, package at hand and relevant dependencies
Python 3.6.7
Pyresample 1.13.2