lets_plot.geom_spoke(mapping=None, *, data=None, position=None, show_legend=None, sampling=None, tooltips=None, arrow=None, pivot=None, color_by=None, **other_args)#

Draw a straight line segment with given length and angle from the starting point.


Set of aesthetic mappings created by aes() function. Aesthetic mappings describe the way that variables in the data are mapped to plot “aesthetics”.

datadict or Pandas or Polars DataFrame

The data to be displayed in this layer. If None, the default, the data is inherited from the plot data as specified in the call to ggplot.

positionstr or FeatureSpec, default=’identity’

Position adjustment. Either a position adjustment name: ‘dodge’, ‘dodgev’, ‘jitter’, ‘nudge’, ‘jitterdodge’, ‘fill’, ‘stack’ or ‘identity’, or the result of calling a position adjustment function (e.g., position_dodge() etc.).

show_legendbool, default=True

False - do not show legend for this layer.


Result of the call to the sampling_xxx() function. To prevent any sampling for this layer pass value “none” (string “none”).


Result of the call to the layer_tooltips() function. Specify appearance, style and content.


Specification for arrow head, as created by arrow() function.

pivot{‘tail’, ‘middle’, ‘mid’, ‘tip’}, default=’tail’

The part of the segment that is anchored to the plane. The segment rotates about this point.

color_by{‘fill’, ‘color’, ‘paint_a’, ‘paint_b’, ‘paint_c’}, default=’color’

Define the color aesthetic for the geometry.


Other arguments passed on to the layer. These are often aesthetics settings used to set an aesthetic to a fixed value, like color=’red’, fill=’blue’, size=3 or shape=21. They may also be parameters to the paired geom/stat.


Geom object specification.


geom_spoke() understands the following aesthetics mappings:

  • x : x-axis value.

  • y : y-axis value.

  • angle : slope’s angle in radians.

  • radius : segment length.

  • alpha : transparency level of a layer. Accept values between 0 and 1.

  • color (colour) : color of the line. String in the following formats: RGB/RGBA (e.g. “rgb(0, 0, 255)”); HEX (e.g. “#0000FF”); color name (e.g. “red”); role name (“pen”, “paper” or “brush”).

  • size : line width.

  • linetype : type of the line. Codes and names: 0 = ‘blank’, 1 = ‘solid’, 2 = ‘dashed’, 3 = ‘dotted’, 4 = ‘dotdash’, 5 = ‘longdash’, 6 = ‘twodash’.


1from lets_plot import *
3ggplot() + geom_spoke(x=0, y=0, angle=0, radius=1)

 1import numpy as np
 2from lets_plot import *
 4n = 21
 5a, b = -1, 1
 6d = (b - a) / (n - 1)
 7space = np.linspace(a, b, n)
 8X, Y = np.meshgrid(space, space)
 9Z = X**2 + Y**2
10dY, dX = np.gradient(Z, d)
11R = np.sqrt(dX**2 + dY**2)
12nR = R / R.max() * d
13A = np.arctan2(dY, dX)
14data = dict(x=X.reshape(-1), y=Y.reshape(-1), z=Z.reshape(-1), r=nR.reshape(-1), a=A.reshape(-1))
15ggplot(data, aes('x', 'y', color='z')) + \
16    geom_spoke(aes(angle='a', radius='r'), \
17               arrow=arrow(type='closed', angle=15)) + \
18    scale_color_gradient(low='#2c7bb6', high='#d7191c') + \
19    coord_fixed()

 1import numpy as np
 2from lets_plot import *
 4n = 10
 5a, b = 10, 30
 6d = (b - a) / (n - 1)
 7space = np.linspace(a, b, n)
 8X, Y = np.meshgrid(space, space)
 9A = np.arctan2(*np.gradient(X * Y, d))
10data = dict(x=X.reshape(-1), y=Y.reshape(-1), a=A.reshape(-1))
11ggplot(data, aes('x', 'y')) + \
12    geom_livemap() + \
13    geom_spoke(aes(angle='a', radius='a'))