Python 如何使用 pyplot.barh() 在每个条上显示条的值？

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

提问by Franck Dernoncourt

I generated a bar plot, how can I display the value of the bar on each bar?

我生成了一个条形图，如何在每个条形上显示条形的值？

Current plot:

当前情节：

What I am trying to get:

我想得到什么：

My code:

我的代码：

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

采纳答案by cphlewis

Add:

添加：

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

result:

结果：

The y-values vare both the x-location and the string values for ax.text, and conveniently the barplot has a metric of 1 for each bar, so the enumeration iis the y-location.

y 值v既是 x 位置，又是 的字符串值ax.text，方便地，条形图的每个条的度量为 1，因此枚举i是 y 位置。

回答by Franck Dernoncourt

I have noticed api example codecontains an example of barchart with the value of the bar displayed on each bar:

我注意到api 示例代码包含一个条形图示例，每个条形上显示条形图的值：

"""
========
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()

output:

输出：

FYI What is the unit of height variable in "barh" of matplotlib?(as of now, there is no easy way to set a fixed height for each bar)

仅供参考matplotlib 的“barh”中的高度变量单位是什么？（截至目前，没有简单的方法可以为每个条设置固定高度）

回答by SaturnFromTitan

I know it's an old thread, but I landed here several times via Google and think no given answer is really satisfying yet. Try using one of the following functions:

我知道这是一个旧线程，但我通过谷歌多次登陆这里，并认为没有给出的答案是真正令人满意的。尝试使用以下功能之一：

EDIT: As I'm getting some likes on this old thread, I wanna share an updated solution as well (basically putting my two previous functions together and automatically deciding whether it's a bar or hbar plot):

编辑：当我在这个旧线程上得到一些喜欢时，我也想分享一个更新的解决方案（基本上将我之前的两个函数放在一起并自动决定它是条形图还是 hbar 形图）：

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)

Now you can use them for regular bar plots:

现在您可以将它们用于常规条形图：

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)

or for horizontal bar plots:

或对于水平条形图：

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)

回答by tozCSS

For pandas people :

对于熊猫人：

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)];

That's it. Alternatively, for those who prefer applyover looping with enumerate:

就是这样。或者，对于那些喜欢apply使用 enumerate 循环的人：

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

Also, ax.patcheswill give you the bars that you would get with ax.bar(...). In case you want to apply the functions of @SaturnFromTitan or techniques of others.

此外，ax.patches会给你你会得到的酒吧ax.bar(...)。如果您想应用@SaturnFromTitan 的功能或其他人的技术。

回答by Skromak

For anyone wanting to have their label at the baseof their bars just divide v by the value of the labellike this:

对于任何想要将标签放在条形底部的人，只需将 v 除以标签的值，如下所示：

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

(note: I added 100 so it wasn't absolutely at the bottom)

（注意：我加了 100 所以它不是绝对在底部）

To get a result like this:

要得到这样的结果：

回答by Haramoz

I needed the bar labels too, note that my y-axis is having a zoomed view using limits on y axis. The default calculations for putting the labels on top of the bar still works using height (use_global_coordinate=False in the example). But I wanted to show that the labels can be put in the bottom of the graph too in zoomed view using global coordinates in matplotlib 3.0.2. Hope it help someone.

我也需要条形标签，请注意我的 y 轴有一个使用 y 轴限制的缩放视图。将标签放在栏顶部的默认计算仍然使用高度（在示例中 use_global_coordinate=False）。但我想表明标签也可以使用matplotlib 3.0.2 中的全局坐标在缩放视图中放在图表的底部。希望它可以帮助某人。

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')

回答by Anirvan Sen

Use plt.text()to put text in the plot.

使用plt.text()将文本放入绘图中。

Example:

例子：

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()

This will show the figure as:

这将显示如下图：

bar chart with values at the top

顶部带有值的条形图