Fundamentals of Dask Transcripts
Chapter: Dask Delayed
Lecture: Best practices and references
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Welcome back to our Daskis and congratulations on making it through that checkpoint.
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Now, I want to tell you about some best practices when using 'Dask Delayed'. Now, there are lots of best practices we could discuss.
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We're going to talk about three now and it's really the handful of ones that we think are probably worth mentioning upfront based on the type of code.
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We see people right all the time with Dask and Dask Delayed to the first point number one, 'Don't call Delayed on the result of a function as it will
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execute immediately', 'Do Call Delayed on the function and then pass the arguments of the function to the code you've written there,
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best practice two, 'compute at once instead of repeatedly'. So here we see that we're calling, compute within a for loop. Let's avoid that completely.
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So what we want to do is collect as many delayed calls as possible for one
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compute so we look through them here and then we pass them to 'dask.compute( )' there. Now, the third one,
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this is worth spending a moment on because we've usually seen functions passed to the Delayed wrapper. Instead of doing that.
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When defining a function, you can add the '@dask.delayed' decorator at the top
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which pretty much does the same as passing a function to the delayed rapper. Now the best practice here is do not mutate inputs in the function,
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so don't do this mutation here within the function. Okay. What the best practices is to return the new value or to return copies
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Okay, so for more best practices, I'd encourage you to refer to the Dask documentation. Now to wrap up.
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We have included some references below of what we think are some pretty cool documentation and
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tutorials on Dask Delay. See you back here soon for the next video.