如何在情节中结合 .add_annotation 和 go.Layout？答案

【问题标题】：How to combine .add_annotation and go.Layout in plotly?如何在情节中结合 .add_annotation 和 go.Layout？
【发布时间】：2021-08-10 09:31:03
【问题描述】：

请问如何将显示文本的命令与 go.Layout 结合起来？当 go.Layout() 存在时，命令 fig.add_annotation 停止工作。 go.Layout 包含很多功能；因此，我不想改变它。

import pandas as pd
import plotly.express as px
import plotly.graph_objects as go

## sample DataFrames
df1=pd.DataFrame({'A':[1,2,3],'B':[4,5,6]})


fig = px.scatter(df1, x='A', y='B')

fig.add_annotation(text="Absolutely-positioned annotation",
                  x=2.5, y=4.5, showarrow=False)

layout = go.Layout(
    template = "plotly_white",
    title="<b>O-C diagram</b>",
    font_family="Trebuchet",
    title_font_family="Trebuchet",
    title_font_color="Navy",
    xaxis_tickformat = "5.0",
    yaxis_tickformat = ".1f",
    xaxis2 = XAxis( 
        overlaying='x',
        side='top',
    ),
    legend=dict(
        yanchor="top",
        y=0.99,
        xanchor="left",
        x=0.83,
    font=dict(
        family="Trebuchet",
        size=20,
        color="black"
     ),
        bgcolor="LightGray",
        bordercolor="Black",
        borderwidth=0
     ),
    xaxis_title=r'<i>T</i>',
    yaxis_title=r'O',
    title_x=0.5,
    font=dict(
        family="Trebuchet",
        size=26,
        color="Black"
    ),
)

fig.layout = layout

fig.show()

【问题讨论】：

标签： python text layout plotly

【解决方案1】：

这里的问题不是你正在使用：

layout = go.Layout(
    template = "plotly_white",
)

而是……

fig.layout = layout

...覆盖除template 之外的所有布局属性。

如果您改为使用：

fig.update_layout(template = "plotly_white")

然后你会得到：

完整代码：

import pandas as pd
import plotly.express as px
import plotly.graph_objects as go

## sample DataFrames
df1=pd.DataFrame({'A':[1,2,3],'B':[4,5,6]})


fig = px.scatter(df1, x='A', y='B')


fig.add_annotation(text="Absolutely-positioned annotation",
                  x=2.5, y=4.5, showarrow=False)

# layout = go.Layout(
#     template = "plotly_white",
# )

# fig.layout = layout
fig.update_layout(template = "plotly_white")
fig.show()

编辑 - 另一个建议

如果您出于某种原因需要坚持原来的设置，那么只需更改您为图形分配模板和注释的顺序：

import pandas as pd
import plotly.express as px
import plotly.graph_objects as go

## sample DataFrames
df1=pd.DataFrame({'A':[1,2,3],'B':[4,5,6]})


fig = px.scatter(df1, x='A', y='B')


layout = go.Layout(
    template = "plotly_white",
)

fig.layout = layout
fig.add_annotation(text="Absolutely-positioned annotation",
                  x=2.5, y=4.5, showarrow=False)

fig.show()

【讨论】：