"""Utilities for testing with shapely geometries."""
from functools import partial
import numpy as np
import shapely
__all__ = ["assert_geometries_equal"]
def _equals_exact_with_ndim(x, y, tolerance):
dimension_equals = shapely.get_coordinate_dimension(
x
) == shapely.get_coordinate_dimension(y)
with np.errstate(invalid="ignore"):
# Suppress 'invalid value encountered in equals_exact' with nan coordinates
geometry_equals = shapely.equals_exact(x, y, tolerance=tolerance)
return dimension_equals & geometry_equals
def _replace_nan(arr):
return np.where(np.isnan(arr), 0.0, arr)
def _assert_nan_coords_same(x, y, tolerance, err_msg, verbose):
x, y = np.broadcast_arrays(x, y)
x_coords = shapely.get_coordinates(x, include_z=True)
y_coords = shapely.get_coordinates(y, include_z=True)
# Check the shapes (condition is copied from numpy test_array_equal)
if x_coords.shape != y_coords.shape:
return False
# Check NaN positional equality
x_id = np.isnan(x_coords)
y_id = np.isnan(y_coords)
if not (x_id == y_id).all():
msg = build_err_msg(
[x, y],
err_msg + "\nx and y nan coordinate location mismatch:",
verbose=verbose,
)
raise AssertionError(msg)
# If this passed, replace NaN with a number to be able to use equals_exact
x_no_nan = shapely.transform(x, _replace_nan, include_z=True)
y_no_nan = shapely.transform(y, _replace_nan, include_z=True)
return _equals_exact_with_ndim(x_no_nan, y_no_nan, tolerance=tolerance)
def _assert_none_same(x, y, err_msg, verbose):
x_id = shapely.is_missing(x)
y_id = shapely.is_missing(y)
if not (x_id == y_id).all():
msg = build_err_msg(
[x, y],
err_msg + "\nx and y None location mismatch:",
verbose=verbose,
)
raise AssertionError(msg)
# If there is a scalar, then here we know the array has the same
# flag as it everywhere, so we should return the scalar flag.
if x.ndim == 0:
return bool(x_id)
elif y.ndim == 0:
return bool(y_id)
else:
return y_id
def assert_geometries_equal(
x,
y,
tolerance=1e-7,
equal_none=True,
equal_nan=True,
normalize=False,
err_msg="",
verbose=True,
):
"""Raise an AssertionError if two geometry array_like objects are not equal.
Given two array_like objects, check that the shape is equal and all elements
of these objects are equal. An exception is raised at shape mismatch or
conflicting values. In contrast to the standard usage in shapely, no
assertion is raised if both objects have NaNs/Nones in the same positions.
Parameters
----------
x, y : Geometry or array_like
Geometry or geometries to compare.
tolerance: float, default 1e-7
The tolerance to use when comparing geometries.
equal_none : bool, default True
Whether to consider None elements equal to other None elements.
equal_nan : bool, default True
Whether to consider nan coordinates as equal to other nan coordinates.
normalize : bool, default False
Whether to normalize geometries prior to comparison.
err_msg : str, optional
The error message to be printed in case of failure.
verbose : bool, optional
If True, the conflicting values are appended to the error message.
"""
__tracebackhide__ = True # Hide traceback for py.test
if normalize:
x = shapely.normalize(x)
y = shapely.normalize(y)
x = np.asarray(x)
y = np.asarray(y)
is_scalar = x.ndim == 0 or y.ndim == 0
# Check the shapes (condition is copied from numpy test_array_equal)
if not (is_scalar or x.shape == y.shape):
msg = build_err_msg(
[x, y],
err_msg + f"\n(shapes {x.shape}, {y.shape} mismatch)",
verbose=verbose,
)
raise AssertionError(msg)
flagged = False
if equal_none:
flagged = _assert_none_same(x, y, err_msg, verbose)
if not np.isscalar(flagged):
x, y = x[~flagged], y[~flagged]
# Only do the comparison if actual values are left
if x.size == 0:
return
elif flagged:
# no sense doing comparison if everything is flagged.
return
is_equal = _equals_exact_with_ndim(x, y, tolerance=tolerance)
if is_scalar and not np.isscalar(is_equal):
is_equal = bool(is_equal[0])
if np.all(is_equal):
return
elif not equal_nan:
msg = build_err_msg(
[x, y],
err_msg + f"\nNot equal to tolerance {tolerance:g}",
verbose=verbose,
)
raise AssertionError(msg)
# Optionally refine failing elements if NaN should be considered equal
if not np.isscalar(is_equal):
x, y = x[~is_equal], y[~is_equal]
# Only do the NaN check if actual values are left
if x.size == 0:
return
elif is_equal:
# no sense in checking for NaN if everything is equal.
return
is_equal = _assert_nan_coords_same(x, y, tolerance, err_msg, verbose)
if not np.all(is_equal):
msg = build_err_msg(
[x, y],
err_msg + f"\nNot equal to tolerance {tolerance:g}",
verbose=verbose,
)
raise AssertionError(msg)
## BELOW A COPY FROM numpy.testing._private.utils (numpy version 1.20.2)
def build_err_msg(
arrays,
err_msg,
header="Geometries are not equal:",
verbose=True,
names=("x", "y"),
precision=8,
):
msg = ["\n" + header]
if err_msg:
if err_msg.find("\n") == -1 and len(err_msg) < 79 - len(header):
msg = [msg[0] + " " + err_msg]
else:
msg.append(err_msg)
if verbose:
for i, a in enumerate(arrays):
if isinstance(a, np.ndarray):
# precision argument is only needed if the objects are ndarrays
r_func = partial(np.array_repr, precision=precision)
else:
r_func = repr
try:
r = r_func(a)
except Exception as exc:
r = f"[repr failed for <{type(a).__name__}>: {exc}]"
if r.count("\n") > 3:
r = "\n".join(r.splitlines()[:3])
r += "..."
msg.append(f" {names[i]}: {r}")
return "\n".join(msg)