More than 1000 points in dataframe

[educhana]

Any dataset (tested with scatter, line) with more than 1000 points will not show anything.

This works:
px.scatter(data[:1000], x='x', y='y')

This does not show anything:
px.scatter(data[:1001], x='x', y='y')

Is there anyway to configure it? Or is it a bug?

[nicolaskruchten]

This is definitely unusual and doesn't occur for me. Our documentation here https://plot.ly/python/plotly-express/ contains many PX plots with dataframes larger than 1000 points.

Can you describe your environment and/or provide a sample of your data?

[educhana]

Hi,
It's JupyterLab (I can reproduce it with Jupyter notebook also)

Code to reproduce the issue:

import pandas as pd
import plotly.express as px
data = pd.DataFrame(data={'x': range(10000), 'y':range(10000)})
px.scatter(data[:1001], x='x', y='y')

px.version is '0.3.0'
jupyterlab 1.1.1
The version of the notebook server is: 6.0.0
The server is running on this version of Python:
Python 3.7.0 (default, Oct 9 2018, 10:31:47)
[GCC 7.3.0]

All in a centos 6 machine

I've seen an error in the js console:
index.js:220 TypeError: Cannot read property 'regl' of null
at new C (plotly.js:69369)
at e (plotly.js:70218)
at Object.e [as plot] (plotly.js:188096)
at h (plotly.js:126031)
at Object.r.plot (plotly.js:125954)
at r.drawData (plotly.js:118146)
at Object.l.syncOrAsync (plotly.js:107399)
at Object.T [as plot] (plotly.js:112749)
at Object.z [as newPlot] (plotly.js:113019)
at Object.we [as react] (plotly.js:115043)

Looking at the source:

  if (options && options.length) options.positions = options;
  regl = options.regl; // persistent variables

  var gl = regl._gl,
      paletteTexture,
      palette = [],
      paletteIds = {},

Seems like is referencing an OpenGL context?
Interestingly, my navigator has some trouble with opengl (is disabled) due to some weird corporate policies.
Does scatter rely on opengl? AFAIK, shouldn't

[nicolaskruchten]

Ah well that's definitely the problem then :) Yes, px.scatter will automatically switch to GL mode for sufficiently large input. You can disable this by explicitly setting render_mode="svg"

[educhana]

Thanks! This works perfectly, indeed!.

px.scatter(data[:1001], x='x', y='y', render_mode="svg")

Perhaps a warning would be desirable or detecting if gl is enabled?

[artdito]

@nicolaskruchten is there any way not to use webGL in other chart types?
I only see render_mode setting for line, line_polar, scatter and scatter_polar.

Thank you!