更新:现在有一个内置的方法!向下滚动“matplotlib 3.4.0中的新功能”的几个答案。

如果你不能升级到那么远，也不需要太多代码。添加:

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

结果:

y值v是ax的x位置值和字符串值。文本，很方便的是，每个柱形图都有一个度量值1，所以枚举I是y位置。

我试图用堆叠的图条来做到这一点。对我有用的代码是。

# Code to plot. Notice the variable ax.
ax = df.groupby('target').count().T.plot.bar(stacked=True, figsize=(10, 6))
ax.legend(bbox_to_anchor=(1.1, 1.05))

# Loop to add on each bar a tag in position
for rect in ax.patches:
    height = rect.get_height()
    ypos = rect.get_y() + height/2
    ax.text(rect.get_x() + rect.get_width()/2., ypos,
            '%d' % int(height), ha='center', va='bottom')

检查这个链接 Matplotlib画廊 这就是我如何使用autolabel的代码片段。

    def autolabel(rects):
    """Attach a text label above each bar in *rects*, displaying its height."""
    for rect in rects:
        height = rect.get_height()
        ax.annotate('{}'.format(height),
                    xy=(rect.get_x() + rect.get_width() / 2, height),
                    xytext=(0, 3),  # 3 points vertical offset
                    textcoords="offset points",
                    ha='center', va='bottom')
        
temp = df_launch.groupby(['yr_mt','year','month'])['subs_trend'].agg(subs_count='sum').sort_values(['year','month']).reset_index()
_, ax = plt.subplots(1,1, figsize=(30,10))
bar = ax.bar(height=temp['subs_count'],x=temp['yr_mt'] ,color ='g')
autolabel(bar)

ax.set_title('Monthly Change in Subscribers from Launch Date')
ax.set_ylabel('Subscriber Count Change')
ax.set_xlabel('Time')
plt.show()

对于熊猫人来说:

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)];

就是这样。 或者，对于那些更喜欢使用apply而不是enumerate循环的人:

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

同时,斧头。Patches将为您提供与ax.bar(…)相同的条形图。如果你想应用@SaturnFromTitan的功能或其他人的技术。

我知道这是一个老帖子，但我通过谷歌登陆了几次，认为没有给出的答案是真正令人满意的。尝试使用以下函数之一:

编辑:因为我在这个旧线程上得到了一些喜欢，我想分享一个更新的解决方案(基本上把我之前的两个函数放在一起，并自动决定它是一个bar还是hbar plot):

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)

现在你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)

或者对于水平条形图:

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)

我也需要条形标签，注意我的y轴有一个使用y轴限制的缩放视图。将标签放在栏顶的默认计算仍然使用height(示例中的use_global_coordinate=False)。但是我想说明的是，使用matplotlib 3.0.2中的全局坐标，也可以在放大视图中将标签放在图的底部。希望它能帮助到别人。

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')