python - Plotly:如何利用 go.Scatter 等函数的元参数？

Question

本质:

如何在以下设置的上下文中使用 help(go.Scatter) 输出中的 %{data[0[.meta[0]} ？

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考虑一个简单的散点图，如下所示:

plotly :

代码:

import plotly.graph_objects as go
import numpy as np

t = [1,2,3]
fig = go.Figure(data=go.Scatter(x=t, y=t, mode='lines'))
fig.show()

运行 help(go.Scatter) 将给出一个输出，其中可以找到以下内容:

 |      meta
 |          Assigns extra meta information associated with this
 |          trace that can be used in various text attributes.
 |          Attributes such as trace `name`, graph, axis and
 |          colorbar `title.text`, annotation `text`
 |          `rangeselector`, `updatemenues` and `sliders` `label`
 |          text all support `meta`. To access the trace `meta`
 |          values in an attribute in the same trace, simply use
 |          `%{meta[i]}` where `i` is the index or key of the
 |          `meta` item in question. To access trace `meta` in
 |          layout attributes, use `%{data[n[.meta[i]}` where `i`
 |          is the index or key of the `meta` and `n` is the trace
 |          index.

问题:

我只是无法理解以下部分:

To access trace meta in layout attributes, use %{data[n[.meta[i]} where i is the index or key of the meta and n is the trace index.

在这个特定的图中，有一个跟踪，例如可以通过运行fig['data'][0]来访问:

Scatter({
    'mode': 'lines', 'x': [1, 2, 3], 'y': [1, 2, 3]
})

根据帮助文件中有关 meta 的其他信息判断，我认为访问此信息将使我们能够编辑文本属性，例如 sliders 和 label 因为它指出

Attributes such as trace name, graph, axis and colorbar title.text, annotation text rangeselector, updatemenues and sliders label text all support meta.

我尝试过各种方法，例如 fig['%{data[0[.meta[0]}'] 但我怀疑我完全误解了整个概念。谁能举个例子来说明如何在这种情况下使用元参数？

谢谢您的建议!

Answer 1

它看起来像是帮助文件中的类型错误。我认为应该是:%{data[n].meta[i]}.

以下代码设置图窗标题属性:

import plotly.graph_objects as go

meta = ["My Figure 1", "Data"]
t = [1,2,3]
data = go.Scatter(x=t, 
                  y=t, 
                  mode='lines')
layout = {'meta': meta,
          'title': '%{meta[0]}' }

fig = go.Figure(data = data, layout = layout)
fig.show()

或者将元数据放入跟踪中:

import plotly.graph_objects as go

meta = ["My Figure 1", "Data"]
t = [1,2,3]
data = go.Scatter(x=t, 
                  y=t, 
                  mode='lines',
                  meta= meta)
layout = {'title': '%{data[0].meta[0]}' }

fig = go.Figure(data = data, layout = layout)
fig.show()

这两种情况的结果都是: