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I often need to "dot product" a vector with itself. E.g., "(pointB - pointA)^2". But when I do this I see the warning:

Warning, ^ is ambiguous on non square matrices. Use .^ to apply ^ element by element.

Is there a way to get rid of this warning? I know I can do "dot(expr, expr)" instead, but then I have to type the expression twice.

Just follow the hint: replace ^ by .^ like (pointB - pointA).^2

parisse a écrit : ↑

mar. mai 28, 2019 10:40 am

Just follow the hint: replace ^ by .^ like (pointB - pointA).^2

Given the vector [a,b,c], I want to arrive at a^2 + b^2 + c^2.

[a,b,c]^2 does this (but gives a warning).

[a,b,c].^2 gives [a^2, b^2, c^2]. Not good.

I know I can do "[a,b,c]*[a,b,c]" or "sum([a,b,c].^2)", but I was wondering if there's a shorter syntax.

Indeed, sorry. l2norm(v)^2 will do.