def get_bounding_box_area(bounding_box):
crs_4326 = CRS('epsg:4326')
geod_wgs84 = crs_4326.get_geod()
polygon_area_m2, _ = geod_wgs84.geometry_area_perimeter(bounding_box)
polygon_area_km2 = polygon_area_m2 / 1000000.0
return polygon_area_km2
def georef_by_worker(sv_corr: list,
alt: xr.DataArray,
lon: xr.DataArray,
lat: xr.DataArray,
hdng: xr.DataArray,
heave: xr.DataArray,
wline: float,
vert_ref: str,
input_crs: CRS,
horizontal_crs: CRS,
z_offset: float,
vdatum_directory: str = None):
"""
Use the raw attitude/navigation to transform the vessel relative along/across/down offsets to georeferenced
soundings. Will support transformation to geographic and projected coordinate systems and with a vertical
reference that you select.
Parameters
----------
sv_corr
[x, y, z] offsets generated with sv_correct
alt
1d (time) altitude in meters
lon
1d (time) longitude in degrees
lat
1d (time) latitude in degrees
hdng
1d (time) heading in degrees
heave
1d (time) heave in degrees
wline
waterline offset from reference point
vert_ref
vertical reference point, one of ['ellipse', 'vessel', 'waterline']
input_crs
pyproj CRS object, input coordinate reference system information for this run
horizontal_crs
pyproj CRS object, destination coordinate reference system information for this run
z_offset
lever arm from reference point to transmitter
vdatum_directory
if 'NOAA MLLW' 'NOAA MHW' is the vertical reference, a path to the vdatum directory is required here
Returns
-------
list
[xr.DataArray alongtrack offset (time, beam), xr.DataArray acrosstrack offset (time, beam),
xr.DataArray down offset (time, beam), xr.DataArray corrected heave for TX - RP lever arm, all zeros if in 'ellipse' mode (time),
xr.DataArray corrected altitude for TX - RP lever arm, all zeros if in 'vessel' or 'waterline' mode (time)]
"""
g = horizontal_crs.get_geod()
# unpack the sv corrected data output
alongtrack = sv_corr[0]
acrosstrack = sv_corr[1]
depthoffset = sv_corr[2] + z_offset
# generate the corrected depth offset depending on the desired vertical reference
corr_dpth = None
corr_heave = None
corr_altitude = None
if vert_ref in kluster_variables.ellipse_based_vertical_references:
corr_altitude = alt
corr_heave = xr.zeros_like(corr_altitude)
corr_dpth = (depthoffset - corr_altitude.values[:, None]).astype(
np.float32)
elif vert_ref == 'vessel':
corr_heave = heave
corr_altitude = xr.zeros_like(corr_heave)
corr_dpth = (depthoffset + corr_heave.values[:, None]).astype(
np.float32)
elif vert_ref == 'waterline':
corr_heave = heave
corr_altitude = xr.zeros_like(corr_heave)
corr_dpth = (depthoffset + corr_heave.values[:, None] - wline).astype(
np.float32)
# get the sv corrected alongtrack/acrosstrack offsets stacked without the NaNs (arrays have NaNs for beams that do not exist in that sector)
at_idx, alongtrack_stck = stack_nan_array(alongtrack,
stack_dims=('time', 'beam'))
ac_idx, acrosstrack_stck = stack_nan_array(acrosstrack,
stack_dims=('time', 'beam'))
# determine the beam wise offsets
bm_azimuth = np.rad2deg(np.arctan2(acrosstrack_stck,
alongtrack_stck)) + np.float32(
hdng[at_idx[0]].values)
bm_radius = np.sqrt(acrosstrack_stck**2 + alongtrack_stck**2)
pos = g.fwd(lon[at_idx[0]].values, lat[at_idx[0]].values,
bm_azimuth.values, bm_radius.values)
z = np.around(corr_dpth, 3)
if vert_ref == 'NOAA MLLW':
sep, vdatum_unc = transform_vyperdatum(
pos[0],
pos[1],
xr.zeros_like(z),
input_crs.to_epsg(),
'mllw',
vdatum_directory=vdatum_directory)
elif vert_ref == 'NOAA MHW':
sep, vdatum_unc = transform_vyperdatum(
pos[0],
pos[1],
xr.zeros_like(z),
input_crs.to_epsg(),
'mhw',
vdatum_directory=vdatum_directory)
else:
sep = 0
vdatum_unc = xr.zeros_like(z)
z = z - sep
if horizontal_crs.is_projected:
# Transformer.transform input order is based on the CRS, see CRS.geodetic_crs.axis_info
# - lon, lat - this appears to be valid when using CRS from proj4 string
# - lat, lon - this appears to be valid when using CRS from epsg
# use the always_xy option to force the transform to expect lon/lat order
georef_transformer = Transformer.from_crs(input_crs,
horizontal_crs,
always_xy=True)
newpos = georef_transformer.transform(
pos[0], pos[1], errcheck=True) # longitude / latitude order (x/y)
else:
newpos = pos
x = reform_nan_array(np.around(newpos[0], 3), at_idx, alongtrack.shape,
alongtrack.coords, alongtrack.dims)
y = reform_nan_array(np.around(newpos[1], 3), ac_idx, acrosstrack.shape,
acrosstrack.coords, acrosstrack.dims)
return [x, y, z, corr_heave, corr_altitude, vdatum_unc]
