def test_landmask_contains():
delete_mask()
l = Landmask()
onland = (np.array([15.]), np.array([65.6]))
assert l.contains(onland[0], onland[1])
onland = (np.array([10.]), np.array([60.0]))
assert l.contains(onland[0], onland[1])
onocean = (np.array([5.]), np.array([65.6]))
assert not l.contains(onocean[0], onocean[1])
l.contains([180], [90])
l.contains([-180], [90])
l.contains([180], [-90])
l.contains([-180], [-90])
def test_tromsoe(tmpdir):
delete_mask()
# xmin, ymin, xmax, ymax
extent = [18.64, 69.537, 19.37, 69.91]
l = Landmask(extent)
lon = np.arange(18.8, 18.969, .0003)
lat = np.arange(69.59, 69.70, .0003)
xx, yy = np.meshgrid(lon, lat)
c = l.contains(xx.ravel(), yy.ravel(), True)
c = c.reshape(xx.shape)
print("c:", c)
import cartopy
import cartopy.crs as ccrs
import matplotlib.pyplot as plt
import os
plt.figure(dpi=200)
ax = plt.axes(projection=ccrs.PlateCarree())
# ax.contourf(lon, lat, c, transform = ccrs.PlateCarree())
ax.imshow(c,
extent=[np.min(lon),
np.max(lon),
np.min(lat),
np.max(lat)],
transform=ccrs.PlateCarree())
reader = cartopy.feature.GSHHSFeature('f') \
.intersecting_geometries([
extent[0],
extent[2],
extent[1],
extent[3]])
ax.add_geometries(list(reader), ccrs.PlateCarree(), alpha=.5)
ax.coastlines()
# ax.set_global()
plt.savefig(os.path.join(tmpdir, 'tromsoe.png'))
def test_norway(tmpdir):
delete_mask()
l = Landmask(extent=[-1, 44, 41, 68])
lon = np.arange(0, 40, .1)
lat = np.arange(45, 67, .1)
xx, yy = np.meshgrid(lon, lat)
c = l.contains(xx.ravel(), yy.ravel())
c = c.reshape(xx.shape)
print("c:", c)
import cartopy.crs as ccrs
import matplotlib.pyplot as plt
import os
plt.figure(dpi=200)
ax = plt.axes(projection=ccrs.PlateCarree())
# ax.contourf(lon, lat, c, transform = ccrs.PlateCarree())
ax.imshow(c, extent=[0, 40, 45, 67], transform=ccrs.PlateCarree())
ax.coastlines()
ax.set_global()
plt.savefig(os.path.join(tmpdir, 'norway.png'))
class Reader(BaseReader):
"""
The global landmask reader is based on the coastline data from
GSHHG (https://www.ngdc.noaa.gov/mgg/shorelines/) optimized for
checking against landmasks.
Args:
:param extent: minx, miny, maxx, maxy bounding box in source CRS for which to include
geometries. Default None (all geometries).
:type extent: array of floats, optional
:param llcrnrlon: minx.
:type llcrnrlon: float, optional, deprecated in favor of extent.
:param llcrnrlat: miny.
:type llcrnrlat: float, optional, deprecated in favor of extent.
:param urcrnrlon: maxx.
:type urcrnrlon: float, optional, deprecated in favor of extent.
:param urcrnrlat: maxy.
:type urcrnrlat: float, optional, deprecated in favor of extent.
:param skippoly: use only rasterized landmask to determine whether points are on land.
:type skippoly: bool, optional, default False.
"""
name = 'global_landmask'
return_block = False
variables = ['land_binary_mask']
proj4 = None
crs = None
skippoly = False
def __init__(self,
extent = None,
llcrnrlon = None,
llcrnrlat = None,
urcrnrlon = None,
urcrnrlat = None,
skippoly = False):
self.proj4 = '+proj=lonlat +ellps=WGS84'
self.crs = pyproj.CRS(self.proj4)
self.skippoly = skippoly
super (Reader, self).__init__ ()
# Depth
self.z = None
if extent and (llcrnrlat or llcrnrlon or urcrnrlat or urcrnrlon):
raise Exception ("'extent' cannot be given togheter with any of 'llcrnrlon', ..'")
elif extent is None and (llcrnrlat or llcrnrlon or urcrnrlat or urcrnrlon):
warnings.warn("llcrnrlon, llcrnrlat, et. al. is deprecated for the global landmask reader. Prefer 'extent' in stead.", DeprecationWarning)
extent = [llcrnrlon, llcrnrlat, urcrnrlon, urcrnrlat]
# Read and store min, max and step of x and y
if extent is not None:
self.xmin, self.ymin, self.xmax, self.ymax = extent
else:
self.xmin, self.ymin = -180, -90
self.xmax, self.ymax = 180, 90
self.xmin, self.ymin = self.lonlat2xy(self.xmin, self.ymin)
self.xmax, self.ymax = self.lonlat2xy(self.xmax, self.ymax)
# setup landmask
self.mask = Landmask(extent, skippoly)
def __on_land__(self, x, y):
return self.mask.contains (x, y, skippoly = self.skippoly, checkextent = False)
def get_variables(self, requestedVariables, time = None,
x = None, y = None, z = None, block = False):
"""
Get binary mask of whether elements are on land or not.
Args:
x (deg[]): longitude (decimal degrees)
y (deg[]): latitude (decimal degrees)
...
x, y is given in reader local projection.
Returns:
Binary mask of point x, y on land.
"""
self.check_arguments(requestedVariables, time, x, y, z)
return { 'land_binary_mask': self.__on_land__(x,y) }