将面板添加到matplotlib中的条形图

Question

如何将包含(每个算法的改进百分比)的面板添加到此条形图？例如，它应该位于图表的右上角。我想这样做是为了让读者更容易看到每个算法与其非贪婪版本相比有多大的改进。

该面板应包含以下内容：

UB-improvement= (("UB+Greedy"- "UB")/"UB")*100
IB-improvement=(("IB+Greedy"- "IB")/"IB")*100
SVD-improvement=(("SVD+Greedy"- "SVD")/"SVD")*100
TOP_N-improvement=(("TOP_N+Greedy"- "TOP_N")/"TOP_N")*100

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下面是我的代码：

import numpy as np
import matplotlib.pyplot as plt
N = 1
ind = np.arange(N)  # the x locations for the groups
width = 0.2     # the width of the bars

fig = plt.figure()
ax = plt.subplot(111)
ub = 5444
rects1 = ax.bar(ind, ub, width, color='red')
ub_greedy = 6573
rects2 = ax.bar(ind+width, ub_greedy, width, color='darkviolet')

ib = 1521
rects3 = ax.bar(ind+2*width, ib, width, color='black')
ib_greedy = 5483
rects4 = ax.bar(ind+3*width, ib_greedy, width, color='blue')

svd=553
rects5 = ax.bar(ind+4*width, svd, width, color='grey')
svd_greedy=1225
rects6 = ax.bar(ind+width*5, svd_greedy, width, color='gold')

pop=7
rects7 = ax.bar(ind+width*6, pop, width, color='brown')
pop_greedy=53
rects8 = ax.bar(ind+width*7, pop_greedy, width, color='lime')

ax.set_ylabel('Owner utilities')
ax.set_xticklabels('')

ax.set_xticks(ind+width)
ax.legend((rects1[0], rects2[0], rects3[0],rects4[0],rects5[0], rects6[0], rects7[0],rects8[0]), ('UB','UB+Greedy','IB','IB+Greedy','SVD','SVD+Greedy','TOP_N','TOP_N+Greedy') ,loc='upper center', bbox_to_anchor=(0.5, -0.05),
          fancybox=True, shadow=True, ncol=8)

def autolabel(rects):
    for rect in rects:
        h = rect.get_height()
        ax.text(rect.get_x()+rect.get_width()/1.9, 1.01*h, '%d'%int(h),
                ha='center', va='bottom')

autolabel(rects1)
autolabel(rects2)
autolabel(rects3)
autolabel(rects4)
autolabel(rects5)
autolabel(rects6)
autolabel(rects7)
autolabel(rects8)

plt.title("Total owner utilities for different algorithms",y=1.08)
plt.show()

Answer 1

在autolabel(rects1)行之前添加以下代码。(我使用python 3)

我使用了automatically position text box in matplotlib

from matplotlib.offsetbox import AnchoredText
def func(greedy, non_greedy): return (greedy - non_greedy)/non_greedy*100

anchored_text = AnchoredText('UB-improvement={:.4}%\n'.format(func(ub_greedy, ub))+
'IB-improvement={:.4}%\n'.format(func(ib_greedy, ib))+
'SVD-improvement={:.4}%\n'.format(func(svd_greedy, svd))+
'TOP_N-improvement={:.4}%\n'.format(func(pop_greedy, pop)), loc=1)
ax.add_artist(anchored_text)