code: def geom_spoke(
      mapping=None,
      *,
      data=None,
      position=None,
      show_legend=None,
      sampling=None,
      tooltips=None,
      pivot=None,
      color_by=None,
      **other_args,
  ):
      """
      Draw a straight line segment with given length and angle from the starting point.
  
      Parameters
      ----------
      mapping : `FeatureSpec`
          Set of aesthetic mappings created by `aes()` function.
          Aesthetic mappings describe the way that variables in the data are
          mapped to plot "aesthetics".
      data : dict 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.
      position : str or `FeatureSpec`, default='identity'
          Position adjustment, either as a string ('identity', 'stack', 'dodge', ...),
          or the result of a call to a position adjustment function.
      show_legend : bool, default=True
          False - do not show legend for this layer.
      sampling : `FeatureSpec`
          Result of the call to the `sampling_xxx()` function.
          To prevent any sampling for this layer pass value "none" (string "none").
      tooltips : `layer_tooltips`
          Result of the call to the `layer_tooltips()` function.
          Specify appearance, style and content.
      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_args
          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.
  
      Returns
      -------
      `LayerSpec`
          Geom object specification.
  
      Notes
      -----
      `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'.
  
      Examples
      --------
      .. jupyter-execute::
          :linenos:
          :emphasize-lines: 3
  
          from lets_plot import *
          LetsPlot.setup_html()
          ggplot() + geom_spoke(x=0, y=0, angle=0, radius=1)
  
      |
  
      .. jupyter-execute::
          :linenos:
          :emphasize-lines: 17
  
          import numpy as np
          from lets_plot import *
          LetsPlot.setup_html()
          n = 21
          a, b = -1, 1
          d = (b - a) / (n - 1)
          space = np.linspace(a, b, n)
          X, Y = np.meshgrid(space, space)
          Z = X**2 + Y**2
          dY, dX = np.gradient(Z, d)
          R = np.sqrt(dX**2 + dY**2)
          nR = R / R.max() * d
          A = np.arctan2(dY, dX)
          data = dict(x=X.reshape(-1), y=Y.reshape(-1), z=Z.reshape(-1), r=nR.reshape(-1), a=A.reshape(-1))
          ggplot(data, aes('x', 'y', color='z')) + \\
              geom_point(size=1.5) + \\
              geom_spoke(aes(angle='a', radius='r')) + \\
              scale_color_gradient(low='#2c7bb6', high='#d7191c') + \\
              coord_fixed()
  
      """
      return _geom(
          "spoke",
          mapping=mapping,
          data=data,
          stat=None,
          position=position,
          show_legend=show_legend,
          sampling=sampling,
          tooltips=tooltips,
          pivot=pivot,
          color_by=color_by,
          **other_args,
      )
  
imports: from lets_plot.geo_data_internals.utils import is_geocoder
  from .core import FeatureSpec, LayerSpec
  from .util import as_annotated_data, is_geo_data_frame, geo_data_frame_to_crs, get_geo_data_frame_meta
label_desc: Use image node_id 40 for calling a global function with example usage: geom_spoke(mapping) and returns: _geom