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python-3.xpython-polarsrust-polars

Polars show_graph method


I am starting to use Polars as a replacement for Pandas. I am very interested in using the show_graph() method to my team to show some of the benefits. One of the biggest benefits I can see is the use of scan_csv. However I am seeing some oddities that I cannot explain. I have the following code using the iris data set.

import polars as pl

x = pl.scan_csv('iris.csv')
x.show_graph()

x = pl.scan_csv('iris.csv').filter(pl.col('variety') == "Setosa").select("petal.length").sum()
x.show_graph()

I am getting random pi and sigma characters. Can anyone explain what the pi and sigma mean? In addition is there a way to ensure that the boxes expand to show all of the information (the csv scan box appears to be cut off in the second show_graph() call. enter image description here


Solution

  • The sigmas and pis aren't random. They're from SQL nomenclature. See here

    The sigma is a selection criteria and the pi is an attribute list.

    As to the sizing, the docs show there's a figsize parameter whose default is (16.0, 12.0) so maybe try with (32.0, 12.0) and try different settings there.