84 lines
2.7 KiB
Python
84 lines
2.7 KiB
Python
![]() |
# Sebastian Raschka 2014-2020
|
||
|
# mlxtend Machine Learning Library Extensions
|
||
|
#
|
||
|
# A function for plotting decision regions of classifiers.
|
||
|
# Author: Sebastian Raschka <sebastianraschka.com>
|
||
|
#
|
||
|
# License: BSD 3 clause
|
||
|
|
||
|
import matplotlib.pyplot as plt
|
||
|
import numpy as np
|
||
|
|
||
|
|
||
|
def ecdf(x, y_label='ECDF', x_label=None, ax=None, percentile=None,
|
||
|
ecdf_color=None, ecdf_marker='o', percentile_color='black',
|
||
|
percentile_linestyle='--'):
|
||
|
"""Plots an Empirical Cumulative Distribution Function
|
||
|
|
||
|
Parameters
|
||
|
----------
|
||
|
x : array or list, shape=[n_samples,]
|
||
|
Array-like object containing the feature values
|
||
|
y_label : str (default='ECDF')
|
||
|
Text label for the y-axis
|
||
|
x_label : str (default=None)
|
||
|
Text label for the x-axis
|
||
|
ax : matplotlib.axes.Axes (default: None)
|
||
|
An existing matplotlib Axes. Creates
|
||
|
one if ax=None
|
||
|
percentile : float (default=None)
|
||
|
Float between 0 and 1 for plotting a percentile
|
||
|
threshold line
|
||
|
ecdf_color : matplotlib color (default=None)
|
||
|
Color for the ECDF plot; uses matplotlib defaults
|
||
|
if None
|
||
|
ecdf_marker : matplotlib marker (default='o')
|
||
|
Marker style for the ECDF plot
|
||
|
percentile_color : matplotlib color (default='black')
|
||
|
Color for the percentile threshold if percentile is not None
|
||
|
percentile_linestyle : matplotlib linestyle (default='--')
|
||
|
Line style for the percentile threshold if percentile is not None
|
||
|
|
||
|
Returns
|
||
|
---------
|
||
|
ax : matplotlib.axes.Axes object
|
||
|
percentile_threshold : float
|
||
|
Feature threshold at the percentile or None if `percentile=None`
|
||
|
percentile_count : Number of if percentile is not None
|
||
|
Number of samples that have a feature less or equal than
|
||
|
the feature threshold at a percentile threshold
|
||
|
or None if `percentile=None`
|
||
|
|
||
|
Examples
|
||
|
-----------
|
||
|
For usage examples, please see
|
||
|
http://rasbt.github.io/mlxtend/user_guide/plotting/ecdf/
|
||
|
|
||
|
"""
|
||
|
if ax is None:
|
||
|
ax = plt.gca()
|
||
|
|
||
|
x = np.sort(x)
|
||
|
y = np.arange(1, x.shape[0] + 1) / float(x.shape[0])
|
||
|
|
||
|
ax.plot(x, y,
|
||
|
marker=ecdf_marker,
|
||
|
linestyle='',
|
||
|
color=ecdf_color)
|
||
|
ax.set_ylabel('ECDF')
|
||
|
if x_label is not None:
|
||
|
ax.set_xlabel(x_label)
|
||
|
if percentile:
|
||
|
targets = x[y <= percentile]
|
||
|
percentile_threshold = targets.max()
|
||
|
percentile_count = targets.shape[0]
|
||
|
ax.axvline(percentile_threshold,
|
||
|
color=percentile_color,
|
||
|
linestyle=percentile_linestyle)
|
||
|
|
||
|
else:
|
||
|
percentile_threshold = None
|
||
|
percentile_count = None
|
||
|
|
||
|
return ax, percentile_threshold, percentile_count
|