基于类别的绘图中单线图的不同颜色（绿色＆amp; red）

Question

有两个数值列是正弦数据。应该绘制为 X轴为TAG，NUM1和NUM2作为Y轴。 NUM1的颜色应按照num1_color进行更改。同样，对于num2和num2_color列。以下是预期的情节。

可复制的代码如下：

示例数据

import pandas as pd
import numpy as np

# create sample dataframe
ty =  pd.DataFrame()
ty['tag'] = [1,2,3,4,5,6,7,8,9,10,11]
ty['num1'] = [0.0, 0.9096319953545183, 0.7557495743542583, -0.2817325568414294,
 -0.9898214418809327, -0.5406408174555974, 0.5406408174555971, 0.9898214418809328,
 0.2817325568414299, -0.7557495743542577, -0.9096319953545183]
ty['num1_color'] = np.where(ty['num1'] >ty['num1'].shift(1) , 'G' , 'R')
ty['num2'] = [0.0, 0.9898214418809328, -0.2817325568414294, -0.9096319953545186,
 0.5406408174555971, 0.7557495743542594, -0.7557495743542577, -0.5406408174555977,
 0.9096319953545179, 0.28173255684143184, -0.9898214418809322]
ty['num2_color'] = np.where(ty['num2'] >ty['num2'].shift(1) , 'G' , 'R')

# display(ty)
    tag      num1 num1_color      num2 num2_color
0     1  0.000000          R  0.000000          R
1     2  0.909632          G  0.989821          G
2     3  0.755750          R -0.281733          R
3     4 -0.281733          R -0.909632          R
4     5 -0.989821          R  0.540641          G
5     6 -0.540641          G  0.755750          G
6     7  0.540641          G -0.755750          R
7     8  0.989821          G -0.540641          G
8     9  0.281733          R  0.909632          G
9    10 -0.755750          R  0.281733          R
10   11 -0.909632          R -0.989821          R

绘图

import plotly
import plotly.express as px
import plotly.graph_objects as go
from plotly.subplots import make_subplots


fig = go.Figure()
fig = make_subplots(specs=[[{"secondary_y": True}]])
x = ty['tag'];y1=ty['num1'];y2=ty['num2']
fig.add_trace(go.Scatter(x=x, y=y1,
                         mode='lines',
                         marker_color='blue',
                         name='macd'), secondary_y=False)
fig.add_trace(go.Scatter(x=x, y=y2,
                         mode='lines',
                         marker_color='red',
                         name='signal'), secondary_y=False)
fig.show()

Answer 1

要按值进行颜色代码，该图被分解为两个点之间的图形，并通过比较条件创建。使用数据框架迭代器获取一行和下一行，将条件与这两个行中的数据进行比较，然后设置图形。最后，更新图表以删除重复的传奇项目。

import plotly
import plotly.express as px
import plotly.graph_objects as go
from plotly.subplots import make_subplots

fig = go.Figure()
fig = make_subplots(specs=[[{"secondary_y": True}]])
x = ty['tag'];y1=ty['num1'];y2=ty['num2']

fig.add_trace(go.Scatter(x=x, y=y1,
                         mode='lines',
                         marker_color='blue',
                         name='macd'), secondary_y=False)
for i, row in ty.iterrows():
    if i <= len(ty)-2:
        if row['num2'] < ty.loc[i+1,'num2']:
            colors = 'green'
        else:
            colors = 'red'
        fig.add_trace(go.Scatter(x=[row['tag'], ty.loc[i+1,'tag']],
                                 y=[row['num2'], ty.loc[i+1,'num2']],
                                 mode='lines',
                                 marker_color=colors,
                                 name='signal',
                                ), secondary_y=False)

names = set()
fig.for_each_trace(
    lambda trace:
        trace.update(showlegend=False)
        if (trace.name in names) else names.add(trace.name))
fig.show()