def test_Ease2Transform_init():
Ngrid = Ease2Transform("EASE2_N25km")
assert_is(Ngrid.gridname, "EASE2_N25km")
N31grid = Ease2Transform("EASE2_N3.125km")
assert_is(N31grid.gridname, "EASE2_N3.125km")
Sgrid = Ease2Transform("EASE2_S25km")
assert_is(Sgrid.gridname, "EASE2_S25km")
Tgrid = Ease2Transform("EASE2_T25km")
assert_is(Tgrid.gridname, "EASE2_T25km")
def test_high_res_Ease2Transform_grid_to_geographic():
Ngrid = Ease2Transform("EASE2_N3.125km")
lat, lon = Ngrid.grid_to_geographic(-0.5, -0.5)
assert_almost_equals(lat, -84.634050, places=precision6)
assert_almost_equals(lon, -135., places=precision6)
Sgrid = Ease2Transform("EASE2_S6.25km")
lat, lon = Sgrid.grid_to_geographic(-0.5, -0.5)
assert_almost_equals(lat, 84.634050, places=precision6)
assert_almost_equals(lon, -45., places=precision6)
Tgrid = Ease2Transform("EASE2_T12.5km")
lat, lon = Tgrid.grid_to_geographic(-0.5, -0.5)
assert_almost_equals(lat, 67.057541, places=precision6)
assert_almost_equals(lon, -180., places=precision6)
def test_UL_Ease2Transform_grid_to_map():
Ngrid = Ease2Transform("EASE2_N25km")
x, y = Ngrid.grid_to_map(-0.5, -0.5)
assert_almost_equals(x, -9000000., places=precision6)
assert_almost_equals(y, 9000000., places=precision6)
Sgrid = Ease2Transform("EASE2_S25km")
x, y = Sgrid.grid_to_map(-0.5, -0.5)
assert_almost_equals(x, -9000000., places=precision6)
assert_almost_equals(y, 9000000., places=precision6)
Tgrid = Ease2Transform("EASE2_T25km")
x, y = Tgrid.grid_to_map(-0.5, -0.5)
assert_almost_equals(x, -17367530.44, places=precision6)
assert_almost_equals(y, 6756820.2, places=precision6)
def test_origin_Ease2Transform_grid_to_map():
Ngrid = Ease2Transform("EASE2_N25km")
x, y = Ngrid.grid_to_map(359.5, 359.5)
assert_almost_equals(x, 0., places=precision6)
assert_almost_equals(y, 0., places=precision6)
Sgrid = Ease2Transform("EASE2_S25km")
x, y = Sgrid.grid_to_map(359.5, 359.5)
assert_almost_equals(x, 0., places=precision6)
assert_almost_equals(y, 0., places=precision6)
Tgrid = Ease2Transform("EASE2_T25km")
x, y = Tgrid.grid_to_map(269.5, 693.5)
assert_almost_equals(x, 0., places=precision6)
assert_almost_equals(y, 0., places=precision6)
def test_UL_Ease2Transform_geographic_to_grid():
Ngrid = Ease2Transform("EASE2_N25km")
row, col = Ngrid.geographic_to_grid(-84.634050, -135.)
assert_almost_equals(row, -0.5, places=precision6)
assert_almost_equals(col, -0.5, places=precision6)
Sgrid = Ease2Transform("EASE2_S25km")
row, col = Sgrid.geographic_to_grid(84.634050, -45.)
assert_almost_equals(row, -0.5, places=precision6)
assert_almost_equals(col, -0.5, places=precision6)
Tgrid = Ease2Transform("EASE2_T25km")
row, col = Tgrid.geographic_to_grid(67.057541, -180.)
assert_almost_equals(row, -0.5, places=precision5)
assert_almost_equals(col, -0.5, places=precision5)
def test_origin_Ease2Transform_geographic_to_grid():
Ngrid = Ease2Transform("EASE2_N25km")
row, col = Ngrid.geographic_to_grid(90., 0.)
assert_almost_equals(row, 359.5, places=precision6)
assert_almost_equals(col, 359.5, places=precision6)
Sgrid = Ease2Transform("EASE2_S25km")
row, col = Sgrid.geographic_to_grid(-90., 0.)
assert_almost_equals(row, 359.5, places=precision4)
assert_almost_equals(col, 359.5, places=precision4)
Tgrid = Ease2Transform("EASE2_T25km")
row, col = Tgrid.geographic_to_grid(0., 0.)
assert_almost_equals(row, 269.5, places=precision6)
assert_almost_equals(col, 693.5, places=precision6)
def test_UL_Ease2Transform_map_to_grid():
Ngrid = Ease2Transform("EASE2_N25km")
row, col = Ngrid.map_to_grid(-9000000., 9000000.)
assert_almost_equals(row, -0.5, places=precision6)
assert_almost_equals(col, -0.5, places=precision6)
Sgrid = Ease2Transform("EASE2_S25km")
row, col = Sgrid.map_to_grid(-9000000., 9000000.)
assert_almost_equals(row, -0.5, places=precision6)
assert_almost_equals(col, -0.5, places=precision6)
Tgrid = Ease2Transform("EASE2_T25km")
row, col = Tgrid.map_to_grid(-17367530.44, 6756820.2)
assert_almost_equals(row, -0.5, places=precision6)
assert_almost_equals(col, -0.5, places=precision6)
def grid_locations_of_subset(subsetName, lat, lon, cubeDir=None):
gpds = ["EASE2_N3.125km", "EASE2_N6.25km", "EASE2_N25km"]
types = ["3?V-SIR", "1?V-SIR", "1?V-GRD"]
#possibly change to H or V for flexibility
print("Input lat, lon = %.6f, %.6f" % (lat, lon))
rows = np.zeros((3))
cols = np.zeros((3))
for i, (thisGpd, thisType) in enumerate(zip(gpds, types)):
grid = Ease2Transform(thisGpd)
row, col = grid.geographic_to_grid(lat, lon)
print("%15s : row, col = %.6f, %.6f" % (thisGpd, row, col))
# Get the cube offsets
offset_row, offset_col = find_cube_offset(subsetName,
cubeDir=cubeDir,
cubeType=thisType)
subRow = row - offset_row
subCol = col - offset_col
print("%15s(%s): row, col = %.6f, %.6f" %
(subsetName, thisType, subRow, subCol))
rows[i] = subRow
cols[i] = subCol
rows = (rows + 0.5).astype('int32')
cols = (cols + 0.5).astype('int32')
#FIXME: MJB: validate that this routine is returning the correct coordinates
#FIXME: This routine should really return a dict structure, not an array
print(gpds)
print("%d %d %d %d %d %d" %
(cols[0], rows[0], cols[1], rows[1], cols[2], rows[2]))
return (rows, cols)
def test_origin_Ease2Transform_grid_to_geographic():
Ngrid = Ease2Transform("EASE2_N25km")
lat, lon = Ngrid.grid_to_geographic(359.5, 359.5)
assert_almost_equals(lat, 90., places=precision6)
assert_almost_equals(lon, 0., places=precision6)
lat, lon = Ngrid.grid_to_geographic(-0.5, -0.5)
assert_almost_equals(lat, -84.634050, places=precision6)
assert_almost_equals(lon, -135., places=precision6)
Sgrid = Ease2Transform("EASE2_S25km")
lat, lon = Sgrid.grid_to_geographic(359.5, 359.5)
assert_almost_equals(lat, -90., places=precision6)
assert_almost_equals(lon, 0., places=precision6)
lat, lon = Sgrid.grid_to_geographic(-0.5, -0.5)
assert_almost_equals(lat, 84.634050, places=precision6)
assert_almost_equals(lon, -45., places=precision6)
Tgrid = Ease2Transform("EASE2_T25km")
lat, lon = Tgrid.grid_to_geographic(269.5, 693.5)
assert_almost_equals(lat, 0., places=precision6)
assert_almost_equals(lon, 0., places=precision6)
lat, lon = Tgrid.grid_to_geographic(-0.5, -0.5)
assert_almost_equals(lat, 67.057541, places=precision6)
assert_almost_equals(lon, -180., places=precision6)
def find_cube_offset(subsetName, cubeDir=None, cubeType=None, verbose=False):
# when no cubeDir is specified, assume it's in a regular
# location on fringe
if not cubeDir:
cubeDir = "%s%s" % ("/mnt/data3/cetb/cubes/AQUA_AMSRE/", subsetName)
if not cubeType:
cubeType = '3*V-SIR'
cubePattern = "%s/CETB.cubefile.%s.*-%s-*-v*.*.TB.nc" % (
cubeDir, subsetName, cubeType)
# Just use the last one found
# Check for no files found and return a reasonable error message
list = glob.glob(cubePattern)
if not list:
raise IOError("No cubefiles found to match the pattern = %s" %
(cubePattern))
else:
cubeFile = list[-1]
print("Reading offset information from cubeFile=%s..." % (cubeFile))
f = Dataset(cubeFile, "r", "NETCDF4")
lats = f.variables['latitude'][:]
lons = f.variables['longitude'][:]
baseGPD = f.variables['crs'].long_name
f.close()
# find and return the baseGPD (row, col) offset for cubeUL(0, 0) location
grid = Ease2Transform(baseGPD)
row_offset, col_offset = grid.geographic_to_grid(lats[0, 0], lons[0, 0])
if verbose:
print("%10s offsets for subsetName=%s and cubeType=%s" %
(baseGPD, subsetName, cubeType))
print(
"(Add these offsets to cube (row, col) to get row, col in full hemisphere)"
)
print("offset row = %f, offset col = %f" % (row_offset, col_offset))
return row_offset, col_offset
# In[2]:
dir(Ease2Transform)
# In[3]:
help(Ease2Transform)
# ### You can instantiate an Ease2Transform object for an EASE-Grid 2.0 projection like this:
# In[4]:
N25 = Ease2Transform("EASE2_N25km")
print N25.gridname
# ### And then call any of the transformation functions like this:
# ### Find the grid coordinates of the North Pole:
# In[5]:
lat, lon = 90., 0.
row, col = N25.geographic_to_grid(lat, lon)
print ("North pole is at:")
print (" geog coordinates lat=%.3f, lon=%.3f" % (lat, lon))
print (" grid coordinates row=%.3f, col=%.3f" % (row, col))