更改时间线中的范围

Question

以下这个问题我想更改X范围（日期），以便从1970年、1980年……到2020年，事件将是a..b等……（我有预定义的事件列表）。我使用以下代码，日期从 1969 年开始，到 1970 年结束（而不是分别是 1970 年和 2020 年）。尝试过的2个选项： '事件': ['a', 'b', 'c', 'd', 'e', 'f'], 第一个选项：

'date':pd.date_range(start='1970', periods=6)

第二个选项：

'date': ['1970', '1980','1990','2000','2010','2020']   

完整代码如下：

import matplotlib.pyplot as plt
import numpy as np
import matplotlib.dates as mdates
from datetime import datetime

df = pd.DataFrame(
    {
        'event': ['a', 'b','c','d','e','f'],
       'date': ['1970','1980','1990','2000','2010','2020']
     # ->   'date':pd.date_range(start='1970', periods=6)
             
    }
)

df['date'] = pd.to_datetime(df['date'])

levels = np.tile(
    [-5, 5, -3, 3, -1, 1],
    int(np.ceil(len(df)/6))
)[:len(df)]

fig, ax = plt.subplots(figsize=(12.8, 4), constrained_layout=True);
ax.set(title="A series of events")

ax.vlines(df['date'], 0, levels, color="tab:red");  # The vertical stems.
ax.plot(   # Baseline and markers on it.
    df['date'],
    np.zeros_like(df['date']),
    "-o",
    color="k",
    markerfacecolor="w"
);

# annotate lines
for d, l, r in zip(df['date'], levels, df['event']):
    ax.annotate(
        r,
        xy=(d, l),
        xytext=(-3, np.sign(l)*3),
        textcoords="offset points",
        horizontalalignment="right",
        verticalalignment="bottom" if l > 0 else "top"
    );

# format xaxis with 4 month intervals
ax.xaxis.set_major_locator(mdates.MonthLocator(interval=4));
ax.xaxis.set_major_formatter(mdates.DateFormatter("%b %Y"));
plt.setp(ax.get_xticklabels(), rotation=30, ha="right");

# remove y axis and spines
ax.yaxis.set_visible(False);
ax.yaxis.set_visible(False);
ax.spines["left"].set_visible(False)
ax.spines["top"].set_visible(False)
ax.spines["right"].set_visible(False)    
ax.margins(y=0.1);
plt.show();

如上所述，我只想在 Xais 上看到 1970 年至 2020 年（没有月份和日期）以及它们各自的事件（a 到 f）。

Answer 1

根据评论和我的理解回答，请参阅下面的完整代码（请注意，我刚刚为

year

添加了一行，并注释掉了

xaxis

部分）：

import matplotlib.pyplot as plt
import numpy as np
import matplotlib.dates as mdates
from datetime import datetime
import pandas as pd

df = pd.DataFrame(
    {
        'event': ['a', 'b','c','d','e','f'],
       'date': ['1970','1980','1990','2000','2010','2020']
     # ->   'date':pd.date_range(start='1970', periods=6)
             
    }
)

df['date'] = pd.to_datetime(df['date'])
df['date'] = df['date'].dt.year # ADDED THIS!

levels = np.tile(
    [-5, 5, -3, 3, -1, 1],
    int(np.ceil(len(df)/6))
)[:len(df)]

fig, ax = plt.subplots(figsize=(12.8, 4), constrained_layout=True);
ax.set(title="A series of events")

ax.vlines(df['date'], 0, levels, color="tab:red");  # The vertical stems.
ax.plot(   # Baseline and markers on it.
    df['date'],
    np.zeros_like(df['date']),
    "-o",
    color="k",
    markerfacecolor="w"
);

# annotate lines
for d, l, r in zip(df['date'], levels, df['event']):
    ax.annotate(
        r,
        xy=(d, l),
        xytext=(-3, np.sign(l)*3),
        textcoords="offset points",
        horizontalalignment="right",
        verticalalignment="bottom" if l > 0 else "top"
    );

# COMMENTED OUT THIS!
# format xaxis with 4 month intervals
# ax.xaxis.set_major_locator(mdates.MonthLocator(interval=4));
# ax.xaxis.set_major_formatter(mdates.DateFormatter("%b %Y"));
plt.setp(ax.get_xticklabels(), rotation=30, ha="right");

# remove y axis and spines
ax.yaxis.set_visible(False);
ax.yaxis.set_visible(False);
ax.spines["left"].set_visible(False)
ax.spines["top"].set_visible(False)
ax.spines["right"].set_visible(False)    
ax.margins(y=0.1);
plt.show();

输出：