def test_write_with_depths(two_triangles, ncds):
"""Tests writing a netcdf file with depth data."""
fname, ncds = ncds
grid = two_triangles
grid.mesh_name = 'mesh1'
gds = Dataset(grid=grid)
# Create a Variable object for the depths:
depths = Variable(name='depth', location='node', data=[1.0, 2.0, 3.0, 4.0])
depths.attributes['units'] = 'm'
depths.attributes['standard_name'] = 'sea_floor_depth_below_geoid'
depths.attributes['positive'] = 'down'
gds.variables['depth'] = depths
gds.save(ncds, format='netcdf4')
ds = netCDF4.Dataset(fname)
assert nc_has_variable(ds, 'mesh1')
assert nc_has_variable(ds, 'depth')
assert nc_var_has_attr_vals(
ds, 'depth', {
'coordinates': 'mesh1_node_lon mesh1_node_lat',
'location': 'node',
'mesh': 'mesh1'
})
ds.close()
def test_write_with_bound_data(two_triangles, ncds):
"""
Tests writing a netcdf file with data on the boundaries
suitable for boundary conditions, for example fluxes.
"""
fname, ncds = ncds
grid = two_triangles
grid.mesh_name = 'mesh3'
gds = Dataset(grid=grid)
# Add the boundary definitions:
grid.boundaries = [(0, 1), (0, 2), (1, 3), (2, 3)]
# Create a Variable object for boundary conditions:
bnds = Variable('bnd_cond', location='boundary', data=[0, 1, 0, 0])
bnds.attributes['long_name'] = 'model boundary conditions'
bnds.attributes['flag_values'] = '0 1'
bnds.attributes['flag_meanings'] = 'no_flow_boundary open_boundary'
gds.variables['bnd_cond'] = bnds
gds.save(ncds)
ds = netCDF4.Dataset(fname)
assert nc_has_variable(ds, 'mesh3')
assert nc_has_variable(ds, 'bnd_cond')
assert nc_var_has_attr_vals(
ds, 'mesh3', {'boundary_node_connectivity': 'mesh3_boundary_nodes'})
assert nc_var_has_attr_vals(
ds, 'bnd_cond', {
'location': 'boundary',
'flag_values': '0 1',
'flag_meanings': 'no_flow_boundary open_boundary',
'mesh': 'mesh3',
})
# There should be no coordinates attribute or variable for the
# boundaries as there is no boundaries_coordinates defined.
assert not nc_has_variable(ds, 'mesh_boundary_lon')
assert not nc_has_variable(ds, 'mesh_boundary_lat')
assert not nc_var_has_attr(ds, 'bnd_cond', 'coordinates')
ds.close()
def test_write_with_edge_data(two_triangles, ncds):
"""Tests writing a netcdf file with data on the edges (fluxes, maybe?)."""
fname, ncds = ncds
two_triangles.mesh_name = 'mesh2'
gds = Dataset(grid=two_triangles)
# Create a Variable object for fluxes:
flux = Variable('flux', location='edge', data=[
0.0,
0.0,
4.1,
0.0,
5.1,
])
flux.attributes['units'] = 'm^3/s'
flux.attributes['long_name'] = 'volume flux between cells'
flux.attributes['standard_name'] = 'ocean_volume_transport_across_line'
gds.variables['flux'] = flux
# Add coordinates for edges.
gds.grid.build_edge_coordinates()
gds.save(ncds)
ds = netCDF4.Dataset(fname)
assert nc_has_variable(ds, 'mesh2')
assert nc_has_variable(ds, 'flux')
assert nc_var_has_attr_vals(
ds, 'flux', {
'coordinates': 'mesh2_edge_lon mesh2_edge_lat',
'location': 'edge',
'units': 'm^3/s',
'mesh': 'mesh2'
})
assert np.array_equal(ds.variables['mesh2_edge_lon'],
gds.grid.edge_coordinates[:, 0])
assert np.array_equal(ds.variables['mesh2_edge_lat'],
gds.grid.edge_coordinates[:, 1])
ds.close()
def test_write_with_velocities(two_triangles, ncds):
"""Tests writing a netcdf file with velocities on the faces."""
fname, ncds = ncds
two_triangles.mesh_name = 'mesh2'
gds = Dataset(grid=two_triangles)
# Create a Variable object for u velocity:
u_vel = Variable('u', location='face', data=[1.0, 2.0])
u_vel.attributes['units'] = 'm/s'
u_vel.attributes['standard_name'] = 'eastward_sea_water_velocity'
gds.variables['u'] = u_vel
# Create a Variable object for v velocity:
v_vel = Variable('v', location='face', data=[3.2, 4.3])
v_vel.attributes['units'] = 'm/s'
v_vel.attributes['standard_name'] = 'northward_sea_water_velocity'
gds.variables['v'] = v_vel
# Add coordinates for face data.
gds.grid.build_face_coordinates()
gds.save(ncds)
ds = netCDF4.Dataset(fname)
assert nc_has_variable(ds, 'mesh2')
assert nc_has_variable(ds, 'u')
assert nc_has_variable(ds, 'v')
assert nc_var_has_attr_vals(
ds, 'u', {
'coordinates': 'mesh2_face_lon mesh2_face_lat',
'location': 'face',
'mesh': 'mesh2',
})
ds.close()
def test_write_everything(twenty_one_triangles, ncds):
"""An example with all features enabled, and a less trivial grid."""
fname, ncds = ncds
grid = twenty_one_triangles
grid.mesh_name = 'mesh'
gds = Dataset(grid=grid)
grid.build_edges()
grid.build_face_face_connectivity()
grid.build_edge_coordinates()
grid.build_face_coordinates()
grid.build_boundary_coordinates()
# Depth on the nodes.
depths = Variable('depth', location='node', data=np.linspace(1, 10, 20))
depths.attributes['units'] = 'm'
depths.attributes['standard_name'] = 'sea_floor_depth_below_geoid'
depths.attributes['positive'] = 'down'
gds.variables['depth'] = depths
# Create a Variable object for u velocity:
u_vel = Variable('u', location='face', data=np.sin(np.linspace(3, 12, 21)))
u_vel.attributes['units'] = 'm/s'
u_vel.attributes['standard_name'] = 'eastward_sea_water_velocity'
gds.variables['u'] = u_vel
# Create a Variable object for v velocity:
v_vel = Variable('v',
location='face',
data=np.sin(np.linspace(12, 15, 21)))
v_vel.attributes['units'] = 'm/s'
v_vel.attributes['standard_name'] = 'northward_sea_water_velocity'
gds.variables['v'] = v_vel
# Fluxes on the edges:
flux = Variable('flux', location='edge', data=np.linspace(1000, 2000, 41))
flux.attributes['units'] = 'm^3/s'
flux.attributes['long_name'] = 'volume flux between cells'
flux.attributes['standard_name'] = 'ocean_volume_transport_across_line'
gds.variables['flux'] = flux
# Boundary conditions:
bounds = np.zeros((19, ), dtype=np.uint8)
bounds[7] = 1
bnds = Variable('bnd_cond', location='boundary', data=bounds)
bnds.attributes['long_name'] = 'model boundary conditions'
bnds.attributes['flag_values'] = '0 1'
bnds.attributes['flag_meanings'] = 'no_flow_boundary open_boundary'
gds.variables['bnd_cond'] = bnds
gds.save(ncds)
ds = netCDF4.Dataset(fname)
# Now the tests:
assert nc_has_variable(ds, 'mesh')
assert nc_has_variable(ds, 'depth')
assert nc_var_has_attr_vals(ds, 'depth', {
'coordinates': 'mesh_node_lon mesh_node_lat',
'location': 'node'
})
assert nc_has_variable(ds, 'u')
assert nc_has_variable(ds, 'v')
assert nc_var_has_attr_vals(
ds, 'u', {
'coordinates': 'mesh_face_lon mesh_face_lat',
'location': 'face',
'mesh': 'mesh'
})
assert nc_var_has_attr_vals(
ds, 'v', {
'coordinates': 'mesh_face_lon mesh_face_lat',
'location': 'face',
'mesh': 'mesh'
})
assert nc_has_variable(ds, 'flux')
assert nc_var_has_attr_vals(
ds, 'flux', {
'coordinates': 'mesh_edge_lon mesh_edge_lat',
'location': 'edge',
'units': 'm^3/s',
'mesh': 'mesh'
})
assert nc_has_variable(ds, 'mesh')
assert nc_has_variable(ds, 'bnd_cond')
assert nc_var_has_attr_vals(
ds, 'mesh', {'boundary_node_connectivity': 'mesh_boundary_nodes'})
assert nc_var_has_attr_vals(
ds, 'bnd_cond', {
'location': 'boundary',
'flag_values': '0 1',
'flag_meanings': 'no_flow_boundary open_boundary',
'mesh': 'mesh'
})
ds.close()
# And make sure pyugrid can reload it!
gds = Dataset(fname)
grid = gds.grid
# And that some things are the same.
# NOTE: more testing might be good here.
# maybe some grid comparison functions?
assert grid.mesh_name == 'mesh'
assert len(grid.nodes) == 20
depth = gds.variables['depth']
assert depth.attributes['units'] == 'm'
u = gds.variables['u']
assert u.attributes['units'] == 'm/s'
def test_save_invalid_format():
ds = Dataset()
with pytest.raises(ValueError):
ds.save("a_filename.txt", format="text")