Operate on several lists to create one list

How do you put corresponding values from different lists together according to some operation?

E.g. I have three lists giving the velocity in the x, y and z direction respectively. I'd like create one list giving the 2-norm, $\sqrt{x^2+y^2+z^2}$.

I would be able to do it procedurally by using for example MapIndexed on one of the lists toghether with Part, I suppose. But I'd like to know if there is a more elegant solution.

Answer

The general way to do this is using MapThread. Using your norm example,

MapThread[Norm[{##}]&, {listX, listY, listZ}]

This particular example has easier solutions though:

Sqrt[ listX^2 + listY^2 + listZ^2 ]

Comments

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