Python: How to get data from related brushes in mlpd3, Bokeh, Plotly?

Question

Using the code below, I can get a 2x2 graph with 4 graphs. With brushes, I can select some data points. I have a question how to get selected data points as a JSON or cvs array. This code uses mlpd3, but bokeh can make similar selections with brushes. But there is no example of data point selection. I am trying to get the selected data as an object to continue processing with python. It would be nice to see the data in the cell.

%matplotlib inline import numpy as np import matplotlib.pyplot as plt import matplotlib as mat import mpld3 mpld3.enable_notebook() from mpld3 import plugins fig, ax = plt.subplots(2, 2, figsize=(10, 8)) fig.subplots_adjust(hspace=0.1, wspace=0.1) ax = ax[::-1] X = np.random.normal(size=(2, 100)) for i in range(2): for j in range(2): ax[i, j].xaxis.set_major_formatter(plt.NullFormatter()) ax[i, j].yaxis.set_major_formatter(plt.NullFormatter()) points = ax[i, j].scatter(X[j], X[i]) plugins.connect(fig, plugins.LinkedBrush(points)) 

Bokeh has similar behavior in CustomJS to select

http://bokeh.pydata.org/en/latest/docs/user_guide/interaction/callbacks.html#userguide-interaction-jscallbacks-customjs-interactions

In any case, it is easier to extract the selected item - it will work. If there is a Plotly solution, this will also work.

Answer 1

This is outside of ipython, but you can run flask or django in conjunction with d3.js and jquery to return the data in python.

Answer 2

You can get the selected data from the Plotly chart using the Plotly new Dash framework .

The docs have an example in the "Graphic Mounting" section https://plot.ly/dash/getting-started-part-2

I have entered the full example below just to save the story.

In each of the callbacks below, you get access to the selected points, the points that you just piled on, or the points that you just clicked on. This application simply displays the values ​​of the points in the application, but you can do something with points (for example, calculate something else).

 import dash from dash.dependencies import Input, Output import dash_core_components as dcc import dash_html_components as html import json app = dash.Dash(__name__) app.layout = html.Div([ dcc.Graph( id='basic-interactions', figure={ 'data': [ { 'x': [1, 2, 3, 4], 'y': [4, 1, 3, 5], 'text': ['a', 'b', 'c', 'd'], 'customdata': ['c.a', 'c.b', 'c.c', 'c.d'], 'name': 'Trace 1', 'mode': 'markers', 'marker': {'size': 12} }, { 'x': [1, 2, 3, 4], 'y': [9, 4, 1, 4], 'text': ['w', 'x', 'y', 'z'], 'customdata': ['c.w', 'c.x', 'c.y', 'c.z'], 'name': 'Trace 2', 'mode': 'markers', 'marker': {'size': 12} } ] } ), html.Div([ dcc.Markdown(""" **Hover Data** Mouse over values in the graph. """.replace(' ', '')), html.Pre(id='hover-data') ], style=styles['column']), html.Div([ dcc.Markdown(""" **Click Data** Click on points in the graph. """.replace(' ', '')), html.Pre(id='click-data'), ], style=styles['column']), html.Div([ dcc.Markdown(""" **Selection Data** Choose the lasso or rectangle tool in the graph menu bar and then select points in the graph. """.replace(' ', '')), html.Pre(id='selected-data'), ]) ]) @app.callback( Output('hover-data', 'children'), [Input('basic-interactions', 'hoverData')]) def display_hover_data(hoverData): # # This is where you can access the hover data # This function will get called automatically when you hover over points # hoverData will be equal to an object with that data # You can compute something off of this data, and return it to the front-end UI # return json.dumps(hoverData, indent=2) @app.callback( Output('click-data', 'children'), [Input('basic-interactions', 'clickData')]) def display_click_data(clickData): # Similarly for data when you click on a point return json.dumps(clickData, indent=2) @app.callback( Output('selected-data', 'children'), [Input('basic-interactions', 'selectedData')]) def display_selected_data(selectedData): # Similarly for data when you select a region return json.dumps(selectedData, indent=2) if __name__ == '__main__': app.run_server(debug=True)