fix(wyh): add plot function (#59)

* fix(wyh): plot function

* fix(wyh): plot function pytest

* fix(wyh):plot function modify comments

* feature(wyh):plot style
Co-authored-by: Nweiyuhong <weiyuhong@sensetime.com>

ding/utils/plot_helper.py

+import numpy as np
+import matplotlib as mpl
+import matplotlib.pyplot as plt
+import seaborn as sns
+
+
+def plot(data: list, xlabel: str, ylabel: str, title: str, pth: str = './picture.jpg'):
+    """
+    Overview:
+        Draw training polyline
+    Interface:
+        data (:obj:`List[Dict]`): the data we will use to draw polylines
+            data[i]['step']: horizontal axis data
+            data[i]['value']: vertical axis data
+            data[i]['label']: the data label
+        xlabel (:obj:`str`): the x label name
+        ylabel (:obj:`str`): the y label name
+        title (:obj:`str`): the title name
+    """
+    sns.set(style="darkgrid", font_scale=1.5)
+    for nowdata in data:
+        step, value, label = nowdata['x'], nowdata['y'], nowdata['label']
+        sns.lineplot(x=step, y=value, label=label)
+    plt.xlabel(xlabel)
+    plt.ylabel(ylabel)
+    plt.title(title)
+    plt.savefig(pth)

ding/utils/tests/test_plot.py

+import random
+import numpy as np
+import os
+import pytest
+
+from ding.utils.plot_helper import plot
+
+
+@pytest.mark.unittest
+def test_plot():
+    rewards1 = np.array([0, 0.1, 0, 0.2, 0.4, 0.5, 0.6, 0.9, 0.9, 0.9])
+    rewards2 = np.array([0, 0, 0.1, 0.4, 0.5, 0.5, 0.55, 0.8, 0.9, 1])
+    rewards = np.concatenate((rewards1, rewards2))  # concatenation array
+    episode1 = range(len(rewards1))
+    episode2 = range(len(rewards2))
+    episode = np.concatenate((episode1, episode2))
+    data1 = {}
+    data1['x'] = episode
+    data1['y'] = rewards
+    data1['label'] = 'line1'
+
+    rewards3 = np.random.random(10)
+    rewards4 = np.random.random(10)
+    rewards = np.concatenate((rewards3, rewards4))  # concatenation array
+    episode3 = range(len(rewards1))
+    episode4 = range(len(rewards2))
+    episode = np.concatenate((episode3, episode4))
+    data2 = {}
+    data2['x'] = episode
+    data2['y'] = rewards
+    data2['label'] = 'line2'
+
+    data = [data1, data2]
+    plot(data, 'step', 'reward_rate', 'test_pic', './pic.jpg')
+    assert os.path.exists('./pic.jpg')

setup.py

@@ -53,6 +53,7 @@ setup(
         'easydict==1.9',
         'tensorboardX>=2.1,<=2.2',
         'matplotlib',  # pypy incompatible
+        'seaborn',
         'yapf==0.29.0',
         'responses~=0.12.1',
         'flask~=1.1.2',