Scatter Plot¶

The traditional scatter plot is mostly used for lower dimensional objective spaces.

Scatter 2D¶

[1]:

from pymoo.visualization.scatter import Scatter
from pymoo.problems import get_problem

F = get_problem("zdt3").pareto_front()
Scatter().add(F).show()

[1]:

<pymoo.visualization.scatter.Scatter at 0x11af31970>

../_images/visualization_scatter_4_1.png

The plot can be further customized by supplying a title, labels, and by using the plotting directives from matplotlib.

[2]:

F = get_problem("zdt3").pareto_front(use_cache=False, flatten=False)
plot = Scatter()
plot.add(F, s=30, facecolors='none', edgecolors='r')
plot.add(F, plot_type="line", color="black", linewidth=2)
plot.show()

[2]:

<pymoo.visualization.scatter.Scatter at 0x11af44cb0>

../_images/visualization_scatter_6_1.png

Scatter 3D¶

[3]:

from pymoo.util.ref_dirs import get_reference_directions

ref_dirs = get_reference_directions("uniform", 3, n_partitions=12)

F = get_problem("dtlz1").pareto_front(ref_dirs)

plot = Scatter()
plot.add(F)
plot.show()

[3]:

<pymoo.visualization.scatter.Scatter at 0x12ac797c0>

../_images/visualization_scatter_8_1.png

Scatter ND / Pairwise Scatter Plots¶

[4]:

import numpy as np
F = np.random.random((30, 4))

plot = Scatter(tight_layout=True)
plot.add(F, s=10)
plot.add(F[10], s=30, color="red")
plot.show()

[4]:

<pymoo.visualization.scatter.Scatter at 0x11af44ce0>

../_images/visualization_scatter_10_1.png

API¶

class pymoo.visualization.scatter.Scatter(self, plot_3d=True, angle=(45, 45), **kwargs)

Scatter Plot

Parameters

axis_styledict: Most of the plots consists of an axis. The style of the axis, e.g. color, alpha, …, can be changed to further modify the plot appealing.
labelsstr or list: The labels to be used for each variable provided in the plot. If a string is used, then they will be enumerated. Otherwise, a list equal to the number of variables can be provided directly.

Other Parameters

figsizetuple: The figure size. Default (figsize=(8, 6)). For some plots changing the size might have side-effects for position.
titlestr or tuple: The title of the figure. If some additional kwargs should be provided this can be achieved by providing a tuple (“name”, {“key” : val}).
legendstr: Whether a legend should be shown or not.
tight_layoutbool: Whether tight layout should be used.