plotly-resampler 0.3.0

Visualizing large time series with plotly

plotly_resampler: visualize large sequential data by adding resampling functionality to Plotly figures

Plotly is an awesome interactive visualization library, however it can get pretty slow when a lot of data points are visualized (100 000+ datapoints). This library solves this by downsampling the data respective to the view and then plotting the downsampled points. When you interact with the plot (panning, zooming, ...), dash callbacks are used to resample and redraw the figures.

In this Plotly-Resampler demo over 110,000,000 data points are visualized!

Installation

pip	pip install plotly-resampler

Usage

To add dynamic resampling to your plotly Figure, you should;

1. wrap the constructor of your plotly Figure with FigureResampler
2. call .show_dash() on the Figure

(OPTIONAL) add the trace data as hf_x and hf_y (for faster initial loading)

Minimal example

import plotly.graph_objects as go; import numpy as np
from plotly_resampler import FigureResampler

x = np.arange(1_000_000)
noisy_sin = (3 + np.sin(x / 200) + np.random.randn(len(x)) / 10) * x / 1_000

fig = FigureResampler(go.Figure())
fig.add_trace(go.Scattergl(name='noisy sine', showlegend=True), hf_x=x, hf_y=noisy_sin)

fig.show_dash(mode='inline')

Features

• Convenient to use:
  • just add the FigureResampler decorator around a plotly Figure constructor and call .show_dash()
  • allows all other ploty figure construction flexibility to be used!
• Environment-independent
  • can be used in Jupyter, vscode-notebooks, Pycharm-notebooks, as application (on a server)
• Interface for various downsampling algorithms:
  • ability to define your preferred sequence aggregation method

Important considerations & tips

• When running the code on a server, you should forward the port of the FigureResampler.show_dash() method to your local machine.
• In general, when using downsampling one should be aware of (possible) aliasing effects.
  The [R] in the legend indicates when the corresponding trace is being resampled (and thus possibly distorted) or not.

Future work 🔨

• Support .add_traces() (currently only .add_trace is supported)

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👤 Jonas Van Der Donckt, Jeroen Van Der Donckt, Emiel Deprost