pyvista.PointSet.threshold_percent

PointSet.threshold_percent(

percent: float = 0.5,

scalars: str | None = None,

invert: bool = False,

continuous: bool = False,

preference: Literal['point', 'cell'] = 'cell',

method: Literal['upper', 'lower'] = 'upper',

progress_bar: bool = False,

)

Threshold the dataset by a percentage of its range on the active scalars array.

Warning

Thresholding is inherently a cell operation, even though it can use associated point data for determining whether to keep a cell. In other words, whether or not a given point is included after thresholding depends on whether that point is part of a cell that is kept after thresholding.

Parameters:

percentfloat | sequence[float], optional

The percentage in the range (0, 1) to threshold. If value is out of 0 to 1 range, then it will be divided by 100 and checked to be in that range.

scalarsstr, optional

Name of scalars to threshold on. Defaults to currently active scalars.

invertbool, default: False

Invert the threshold results. That is, cells that would have been in the output with this option off are excluded, while cells that would have been excluded from the output are included.

continuousbool, default: False

When True, the continuous interval [minimum cell scalar, maximum cell scalar] will be used to intersect the threshold bound, rather than the set of discrete scalar values from the vertices.

preferencestr, default: ‘cell’

When scalars is specified, this is the preferred array type to search for in the dataset. Must be either 'point' or 'cell'. Throughout PyVista, the preference is typically 'point' but since the threshold filter is a cell-wise operation, we prefer cell data for thresholding operations.

methodstr, default: ‘upper’

Set the threshold method for single-values, defining which threshold bounds to use. If the value is a range, this parameter will be ignored, extracting data between the two values. For single values, 'lower' will extract data lower than the value. 'upper' will extract data larger than the value.

progress_barbool, default: False

Display a progress bar to indicate progress.

Returns:

pyvista.UnstructuredGrid

Dataset containing geometry that meets the threshold requirements.

Examples

Apply a 50% threshold filter.

>>> import pyvista as pv
>>> noise = pv.perlin_noise(0.1, (2, 2, 2), (0, 0, 0))
>>> grid = pv.sample_function(
...     noise, [0, 1.0, -0, 1.0, 0, 1.0], dim=(30, 30, 30)
... )
>>> threshed = grid.threshold_percent(0.5)
>>> threshed.plot(
...     cmap='gist_earth_r',
...     show_scalar_bar=False,
...     show_edges=True,
... )

Static Scene

Interactive Scene

Apply a 80% threshold filter.

>>> threshed = grid.threshold_percent(0.8)
>>> threshed.plot(
...     cmap='gist_earth_r',
...     show_scalar_bar=False,
...     show_edges=True,
... )

Static Scene

Interactive Scene

See Using Common Filters for more examples using a similar filter.