It's a good warning in the sense that sometimes you will have variables that you intended to set get into your assignments still undefined and this lets you know, in a non-fatal way, that something may be wrong.

On the other hand, you can do like the Slashdot crew and customize a SIGWARN callback to muffle this output.

In reply to (ichimunki) re x 5: Summing the elements of multiple arrays into a new array by ichimunki
in thread Summing the elements of multiple arrays into a new array by djw

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