Plotly：如何使用匹配行的文本和标记 colors 注释多行的结尾？

Question

The post Plotly: Annotate marker at the last value in line chart shows how to annotate end of lines with text and an individual marker. But how can you do the same thing for multiple lines and at the same time set the associated text and markers to match the color of all lines?

Example plot:

Code with sample dataset:

# imports
import pandas as pd
import plotly.express as px

# data
df = px.data.stocks()
colors = px.colors.qualitative.T10

# plotly
fig = px.line(df, 
                 x = 'date',
                 y = [c for c in df.columns if c != 'date'],
                 template = 'plotly_dark',
                 color_discrete_sequence = colors,
                 title = 'Stocks', 
             )

fig.show()

Answer 1

You can address the features of each trace and build new traces for your end markers and text through:

for i, d in enumerate(fig.data):
    fig.add_scatter(x=[d.x[-1]], y = [d.y[-1]], [...])

If you've specified colors when building your figure you can also retrieve trace colors and set colors for markers and fonts like this:

textfont = dict(color=d.line.color),
marker = dict(color = d.line.color, size = 12)

Plot:

The figure was being a bit crowded so I dropped one of the stocks. I also made room for the annotations by changing the position of the legend through fig.layout.legend.x = -0.3

Complete code:

# imports
import pandas as pd
import plotly.express as px

# data
df = px.data.stocks()
df = df.drop('AMZN', axis = 1)
colors = px.colors.qualitative.T10

# plotly
fig = px.line(df, 
                 x = 'date',
                 y = [c for c in df.columns if c != 'date'],
                 template = 'plotly_dark',
                 color_discrete_sequence = colors,
                 title = 'Stocks', 
             )

# move legend
fig.layout.legend.x = -0.3

# add traces for annotations and text for end of lines
for i, d in enumerate(fig.data):
    fig.add_scatter(x=[d.x[-1]], y = [d.y[-1]],
                    mode = 'markers+text',
                    text = d.y[-1],
                    textfont = dict(color=d.line.color),
                    textposition='middle right',
                    marker = dict(color = d.line.color, size = 12),
                    showlegend=False)

fig.show()