DataObjectFilters.cell_quality

DataObjectFilters.cell_quality#

DataObjectFilters.cell_quality(
quality_measure: Literal['all', 'all_valid'] | _CellQualityLiteral | Sequence[_CellQualityLiteral] = 'scaled_jacobian',
*,
null_value: float = -1.0,
progress_bar: bool = False,
) → _DataSetOrMultiBlockType[source]#

Compute a function of (geometric) quality for each cell of a mesh.

The per-cell quality is added to the mesh’s cell data, in an array with the same name as the quality measure. Cell types not supported by this filter or undefined quality of supported cell types will have an entry of -1.

See the Cell Quality Measures below for all measures and the CellType supported by each one. Defaults to computing the scaled_jacobian quality measure.

Cell Quality Measures#

Measure

TRIANGLE

QUAD

TETRA

HEXAHEDRON

PYRAMID

WEDGE

area

aspect_frobenius

aspect_gamma

aspect_ratio

collapse_ratio

condition

diagonal

dimension

distortion

jacobian

max_angle

max_aspect_frobenius

max_edge_ratio

med_aspect_frobenius

min_angle

oddy

radius_ratio

relative_size_squared

scaled_jacobian

shape

shape_and_size

shear

shear_and_size

skew

stretch

taper

volume

warpage

Note

Refer to the Verdict Library Reference Manual for low-level technical information about how each metric is computed.

Added in version 0.45.

Parameters:
quality_measurestr | sequence[str], default: ‘scaled_jacobian’

The cell quality measures to use. May be either:

  • A single measure or a sequence of measures listed in Cell Quality Measures.

  • 'all' to compute all measures.

  • 'all_valid' to only keep quality measures that are valid for the mesh’s cell types.

A separate array is created for each measure.

null_valuefloat, default: -1.0

Float value for undefined quality. Undefined quality are qualities that could be addressed by this filter but is not well defined for the particular geometry of cell in question, for example, a volume query for a triangle. Undefined quality will always be undefined. The default value is -1.

progress_barbool, default: False

Display a progress bar to indicate progress.

Returns:
outputDataSet | MultiBlock

Dataset with the computed mesh quality. Return type matches input. Cell data arrays with the computed quality measures are included.

Examples#

Download Python source code | Download Jupyter notebook

Compute and plot the minimum angle of a sample sphere mesh.

>>> import pyvista as pv
>>> sphere = pv.Sphere(theta_resolution=20, phi_resolution=20)
>>> cqual = sphere.cell_quality('min_angle')
>>> cqual.plot(show_edges=True)
../../../_images/pyvista-DataObjectFilters-cell_quality-8d2bcf1c68c206a3_00_00.png

Quality measures like 'volume' do not apply to 2D cells, and a null value of -1 is returned.

>>> qual = sphere.cell_quality('volume')
>>> qual.get_data_range('volume')
(np.float64(-1.0), np.float64(-1.0))

Compute all valid quality measures for the sphere. These measures all return non-null values for TRIANGLE cells.

>>> cqual = sphere.cell_quality('all_valid')
>>> valid_measures = cqual.cell_data.keys()
>>> valid_measures
['area',
 'aspect_frobenius',
 'aspect_ratio',
 'condition',
 'distortion',
 'max_angle',
 'min_angle',
 'radius_ratio',
 'relative_size_squared',
 'scaled_jacobian',
 'shape',
 'shape_and_size']

See Also#

cell_quality_info()

Return information about a cell’s quality measure, e.g. acceptable range.

cell_validator()
validate_mesh()