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Python

Posted by Scott Pirrie
Scott Pirrie
1,591 Points

What do the underscores do in this line of code _, (train, valid, test), _ = dc.molnet.load_tox21() ?

I work as a Data Scientist but mainly use R day to day. I'm trying to get my head around python but there are some quirks in the syntax I would like to understand better. Could someone help me understand what they underscores are doing here? Are they wildcard type characters?

1 Answer

Steven Parker
Steven Parker
243,656 Points
Steven Parker
Steven Parker
243,656 Points

I can sympathize with the difficulty of learning a very different computer language. I've never been able to "get my head around" R! :confused:

Underscores are often used in Python as placeholders for unused values.

I'd guess that the "load_tox21" method returns a 3-part tuple, but this code only uses the 2nd part, which is itself another 3-part tuple.

Scott Pirrie
Scott Pirrie
1,591 Points

Hi Steven,

Thanks so much for this! That makes a lot of sense and is actually a really neat piece of functionality!

Much appreciated.

Scott