Average Multiple Curves in Python/v3

Learn how to average the values of multiple curves with Python.


Note: this page is part of the documentation for version 3 of Plotly.py, which is not the most recent version.
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Imports

The tutorial below imports NumPy, Pandas, and SciPy.

In [1]:
import plotly.plotly as py
import plotly.graph_objs as go
from plotly.tools import FigureFactory as FF

import numpy as np
import pandas as pd
import scipy

Average of 2 Curves

Given two curves defined by functions $f$ and $g$ on $\mathbb{R} \rightarrow \mathbb{R}$, the average curve $h$ of $f$ and $g$ is defined by $h = \frac{f(x) + g(x)}{2} $ for $x \in \mathbb{R}$.

In [2]:
x = np.linspace(0, 2*np.pi, 100)
f = np.sin(x)
g = np.cos(x)
h = [(f[j] + g[j])/2 for j in range(len(x))]

trace1 = go.Scatter(
    x=x,
    y=f,
    mode='lines',
    name='f(x)',
    marker=dict(
        color='rgb(220, 20, 60)'
    )
)

trace2 = go.Scatter(
    x=x,
    y=g,
    mode='lines',
    name='g(x)',
    marker=dict(
        color='rgb(100, 149, 237)'
    )
)

trace3 = go.Scatter(
    x=x,
    y=h,
    mode='markers+lines',
    name='Average of f and g',
    marker=dict(
        color='rgb(128, 0, 128)',
        symbol='diamond-open',
    )
)

data = [trace1, trace2, trace3]
py.iplot(data, filename='2-curves')
Out[2]: