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Overplot in plotly in python

How to add a line to a figure? I tried figure.add_, but I do not know what to use for a line. When I reversed the order and used figure.add_scatter, I obtained an error:

The 'cliponaxis' property must be specified as a bool (either True, or False)

import plotly.express as px
import numpy as np
import pandas as pd
from plotly.graph_objs import *
import plotly.graph_objects as go

data_n = np.loadtxt('f.dat', unpack=True, usecols=[0, 2, 5, 7])

data = data_n.tolist()
d = {'A': data[0], 'B': data[1]}

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


x_new = ...
y_new = ...

d_fit = {'x': x_new, 'y': y_new}
df_fit = pd.DataFrame(data=d_fit)

fig = px.line(df_fit, x='x', y='y') # to add

fig.show()
Solution

  • When you call px.scatter or px.line, you pass the DataFrame, and the names of the columns to the parameters x and y. When you call go.Scatter you have to pass column slice sof the DataFrame directly to the x and y parameters. The add_scatter function is a convenience method that performs the same function as adding a graph_object, NOT a plotly express object. Therefore, you have to pass the same parameters to add_scatter as you would to go.Scatter.

    For example, using two sample DataFrames, the following code works:

    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]})
df2=pd.DataFrame({'x':[1,2,3],'y':[7,8,9]})

fig = px.scatter(df1, x='A', y='B')
fig.add_scatter(x=df2['x'], y=df2['y'])
fig.show()

    enter image description here

    But if I replace fig.add_scatter(x=df2['x'], y=df2['y']) with fig.add_scatter(df2, x='x', y='y'), I will get an error:

    ValueError: 
    Invalid value of type 'pandas.core.frame.DataFrame' received for the 'cliponaxis' property of scatter
        Received value:    x  y
0  1  7
1  2  8
2  3  9

The 'cliponaxis' property must be specified as a bool
(either True, or False)

    By the way, I would recommend not using the import statement from plotly.graph_objs import * as this imports all of the functions and classes from plotly including ones you don't need.