关于python:如何使用pyplot.barh()在每个条形上显示条形的值?

How to display the value of the bar on each bar with pyplot.barh()?

我生成了条形图,如何在每个条形上显示条形的值?

当前情节:

enter image description here

我想要得到的是:

enter image description here

我的代码:

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import os
import numpy as np
import matplotlib.pyplot as plt

x = [u'INFO', u'CUISINE', u'TYPE_OF_PLACE', u'DRINK', u'PLACE', u'MEAL_TIME', u'DISH', u'NEIGHBOURHOOD']
y = [160, 167, 137, 18, 120, 36, 155, 130]

fig, ax = plt.subplots()    
width = 0.75 # the width of the bars
ind = np.arange(len(y))  # the x locations for the groups
ax.barh(ind, y, width, color="blue")
ax.set_yticks(ind+width/2)
ax.set_yticklabels(x, minor=False)
plt.title('title')
plt.xlabel('x')
plt.ylabel('y')      
#plt.show()
plt.savefig(os.path.join('test.png'), dpi=300, format='png', bbox_inches='tight') # use format='svg' or 'pdf' for vectorial pictures


加:

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for i, v in enumerate(y):
    ax.text(v + 3, i + .25, str(v), color='blue', fontweight='bold')

结果:

enter image description here

y值v既是x位置,也是ax.text的字符串值,并且方便地,条形图的每个小节的度量均为1,因此枚举i是y位置。


我注意到api示例代码包含一个条形图示例,其中每个条形图上都显示了条形图的值:

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"""
========
Barchart
========

A bar plot with errorbars and height labels on individual bars
"""

import numpy as np
import matplotlib.pyplot as plt

N = 5
men_means = (20, 35, 30, 35, 27)
men_std = (2, 3, 4, 1, 2)

ind = np.arange(N)  # the x locations for the groups
width = 0.35       # the width of the bars

fig, ax = plt.subplots()
rects1 = ax.bar(ind, men_means, width, color='r', yerr=men_std)

women_means = (25, 32, 34, 20, 25)
women_std = (3, 5, 2, 3, 3)
rects2 = ax.bar(ind + width, women_means, width, color='y', yerr=women_std)

# add some text for labels, title and axes ticks
ax.set_ylabel('Scores')
ax.set_title('Scores by group and gender')
ax.set_xticks(ind + width / 2)
ax.set_xticklabels(('G1', 'G2', 'G3', 'G4', 'G5'))

ax.legend((rects1[0], rects2[0]), ('Men', 'Women'))


def autolabel(rects):
   """
    Attach a text label above each bar displaying its height
   """

    for rect in rects:
        height = rect.get_height()
        ax.text(rect.get_x() + rect.get_width()/2., 1.05*height,
                '%d' % int(height),
                ha='center', va='bottom')

autolabel(rects1)
autolabel(rects2)

plt.show()

输出:

enter image description here

仅供参考matplotlib的" barh"中的高度变量的单位是什么? (到目前为止,还没有简单的方法为每个钢筋设置固定高度)


对于任何想要将标签置于其条形底部的人,只需将v除以标签值即可,如下所示:

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for i, v in enumerate(labels):
    axes.text(i-.25,
              v/labels[i]+100,
              labels[i],
              fontsize=18,
              color=label_color_list[i])

(注意:我加了100,所以不是绝对在底部)

要获得这样的结果:
enter image description here


使用plt.text()将文本放入绘图中。

例:

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import matplotlib.pyplot as plt
N = 5
menMeans = (20, 35, 30, 35, 27)
ind = np.arange(N)

#Creating a figure with some fig size
fig, ax = plt.subplots(figsize = (10,5))
ax.bar(ind,menMeans,width=0.4)
#Now the trick is here.
#plt.text() , you need to give (x,y) location , where you want to put the numbers,
#So here index will give you x pos and data+1 will provide a little gap in y axis.
for index,data in enumerate(menMeans):
    plt.text(x=index , y =data+1 , s=f"{data}" , fontdict=dict(fontsize=20))
plt.tight_layout()
plt.show()

该图将显示为:

条形图,值在顶部


我知道这是一个老话题,但是我通过Google登陆了几次,认为还没有一个令人满意的答案。尝试使用以下功能之一:

编辑:当我在这个旧线程上受到喜欢时,我也想分享一个更新的解决方案(基本上将我先前的两个函数放在一起,并自动确定它是条形图还是hbar图):

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def label_bars(ax, bars, text_format, **kwargs):
   """
    Attaches a label on every bar of a regular or horizontal bar chart
   """

    ys = [bar.get_y() for bar in bars]
    y_is_constant = all(y == ys[0] for y in ys)  # -> regular bar chart, since all all bars start on the same y level (0)

    if y_is_constant:
        _label_bar(ax, bars, text_format, **kwargs)
    else:
        _label_barh(ax, bars, text_format, **kwargs)


def _label_bar(ax, bars, text_format, **kwargs):
   """
    Attach a text label to each bar displaying its y value
   """

    max_y_value = ax.get_ylim()[1]
    inside_distance = max_y_value * 0.05
    outside_distance = max_y_value * 0.01

    for bar in bars:
        text = text_format.format(bar.get_height())
        text_x = bar.get_x() + bar.get_width() / 2

        is_inside = bar.get_height() >= max_y_value * 0.15
        if is_inside:
            color ="white"
            text_y = bar.get_height() - inside_distance
        else:
            color ="black"
            text_y = bar.get_height() + outside_distance

        ax.text(text_x, text_y, text, ha='center', va='bottom', color=color, **kwargs)


def _label_barh(ax, bars, text_format, **kwargs):
   """
    Attach a text label to each bar displaying its y value
    Note: label always outside. otherwise it's too hard to control as numbers can be very long
   """

    max_x_value = ax.get_xlim()[1]
    distance = max_x_value * 0.0025

    for bar in bars:
        text = text_format.format(bar.get_width())

        text_x = bar.get_width() + distance
        text_y = bar.get_y() + bar.get_height() / 2

        ax.text(text_x, text_y, text, va='center', **kwargs)

现在,您可以将它们用于常规条形图:

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fig, ax = plt.subplots((5, 5))
bars = ax.bar(x_pos, values, width=0.5, align="center")
value_format ="{:.1%}"  # displaying values as percentage with one fractional digit
label_bars(ax, bars, value_format)

或对于水平条形图:

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fig, ax = plt.subplots((5, 5))
horizontal_bars = ax.barh(y_pos, values, width=0.5, align="center")
value_format ="{:.1%}"  # displaying values as percentage with one fractional digit
label_bars(ax, horizontal_bars, value_format)

对于熊猫人:

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ax = s.plot(kind='barh') # s is a Series (float) in [0,1]
[ax.text(v, i, '{:.2f}%'.format(100*v)) for i, v in enumerate(s)];

而已。
另外,对于那些喜欢apply而不是枚举循环的人:

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it = iter(range(len(s)))
s.apply(lambda x: ax.text(x, next(it),'{:.2f}%'.format(100*x)));

同样,ax.patches将为您提供ax.bar(...)可获得的条形。如果您想应用@SaturnFromTitan的功能或其他技术。


我也需要条形标签,请注意,我的y轴具有使用y轴限制的缩放视图。用于将标签放在条形顶部的默认计算仍然可以使用高度(在示例中为use_global_coordinate = False)。但是我想表明,也可以使用matplotlib 3.0.2中的全局坐标在缩放视图中将标签也放置在图形的底部。希望它能帮助某人。

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def autolabel(rects,data):
"""
Attach a text label above each bar displaying its height
"""

c = 0
initial = 0.091
offset = 0.205
use_global_coordinate = True

if use_global_coordinate:
    for i in data:        
        ax.text(initial+offset*c, 0.05, str(i), horizontalalignment='center',
                verticalalignment='center', transform=ax.transAxes,fontsize=8)
        c=c+1
else:
    for rect,i in zip(rects,data):
        height = rect.get_height()
        ax.text(rect.get_x() + rect.get_width()/2., height,str(i),ha='center', va='bottom')

Example output