stat_streamline ¶

Streamlines of a vector field (stat="streamline"), drawn by geom.

As stat_streamline in the R package metR. Every streamline is its own group of x, y vertices in order; see geom_streamline for how the field is built and the options.

Parameters:

• mapping (FeatureSpec, default: None ) –

  Aesthetic mapping from aes(). Needs x, y, u and v.

• data (DataFrame or dict, default: None ) –

  Layer data; inherits the plot data when None.

• geom (str, default: "streamline" ) –

  Geom that draws the lines, e.g. "path" (with arrow=arrow() for heads at the line ends) or "point" for the vertices.

• position (str or FeatureSpec, default: None ) –

  Position adjustment, applied to the line vertices.

• show_legend (bool, default: None ) –

  False hides this layer from the legend.

• inherit_aes (bool, default: None ) –

  False ignores the plot's default mapping for this layer.

• sampling ((str, int or FeatureSpec), default: None ) –

  Rows to draw: a sampling_*() spec, an int n (sampling_random(n)) or "none". Default: every row.

• tooltips (FeatureSpec or list of str, default: None ) –

  Tooltip content: layer_tooltips(), a list of column names, or "none".

• density (float or tuple of float, default: 1 ) –

  Closeness of the lines (see geom_streamline).

• minlength (float, default: 0.1 ) –

  Shortest line kept, in axes coordinates.

• maxlength (float, default: 4.0 ) –

  Longest line, in axes coordinates.

• integration_direction ((both, forward, backward), default: "both" ) –

  Integrate along the field, against it, or both.

• broken_streamlines (bool, default: True ) –

  Stop a line when it comes too close to another.

• gridded (bool, default: None ) –

  Whether the rows are a regular grid (see geom_streamline).

• grid_density (float, default: 1 ) –

  Scattered rows only: int(50 * grid_density) grid points per axis.

• smooth (float, default: 0.5 ) –

  Scattered rows only: Gaussian kernel width in grid steps.

• n_neighbors (int, default: None ) –

  Scattered rows only: rows per grid point (default int(n_rows / 50)).

• min_mass (float, default: 1 ) –

  Scattered rows only: kernel weight threshold, 10 ** (min_mass - 6).

• cutoff_percentile (float, default: 5 ) –

  Scattered rows only: speed percentile below which grid points are empty.

• na_rm (bool, default: None ) –

  True removes rows with missing values silently.

• **other_args (Any) –

  Constant aesthetics and the geom's options (arrow=arrow()).

Returns:

• LayerSpec –

  The layer.

Raises:

• SpecError –

  If integration_direction is unknown, or a density, smooth or n_neighbors is not positive.

• UnsupportedValueError –

  If an option has the wrong type.

Examples:

>>> from ggrust import *
>>> import numpy as np
>>> east, north = np.meshgrid(np.linspace(-2, 2, 21), np.linspace(-2, 2, 21))
>>> field = {"x": east.ravel(), "y": north.ravel(), "u": -north.ravel(), "v": east.ravel()}
>>> plot = ggplot(field, aes("x", "y", u="u", v="v")) + stat_streamline(
...     geom="path", arrow=arrow(length=5)
... )