PR: Update ArrayEditor to correct deprecated Numpy operator

[GKosiba]

Fixes #4663.

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Changed numpy boolean subract operator '-' to np.logical_xor. As suggested in the numpy deprec warning.
Tested locally with no error originally described in #4663

[ccordoba12]

Is this backwards compatible? I mean, does it work with previous Numpy versions?

[ccordoba12]

And of course. thanks a lot for your contribution!!

[jitseniesen]

What about when the array loaded in the variable explorer does not have boolean entries?

[GKosiba]

Sorry, didn't have a lot of time yesterday, but that wasn't a fix.
Essentially this line is scaling the hue of each index in the pop-up 'array' window relative to the maximum value in the array.

This new edit calculates this scaling factor (max-value)/(max-min) with max as float each time. The issue only occurs for boolean with the deprecated minus operator but float of 0 or 1 minus value of 0 or 1 gives the same value for the scaling factor and was converted to float anyways in the next line.

Tested with bool and non-bool array types and older numpy versions.

[ccordoba12]

@jitseniesen, do you approve this one?

[jitseniesen]

@GKosiba Looks good; but one detail: could you please add a short comment explaining why the conversion to float is there? e.g. "convert to float to handle bool arrays". I am afraid the conversion will puzzle us later.

[GKosiba]

@ccordoba12 @jitseniesen Comment added

[jitseniesen]

Looks good to me. Thanks for your contribution.

[ccordoba12]

Thanks @GKosiba for your contribution and @jitseniesen for reviewing it.

This is going in!