Re: Sqrt discrepancy, Mathematica

Dana wrote:

Would this debugging technique work?

Sqrt[b-a] // Trace


Thanks - it did.
The error appears after loading the "OPScalar" package from
Mathsource/4291. This provides a non-commutative "diamond" operator,
overwriting "**" . I shall now abandon my search for a non-commutative
extension to the determinant function. (I was not getting anywhere with
it.)


Roger Beresford wrote:
In Mathematica 4.2, Sqrt[b-a] prints as -/(b-a) (Sqrt symbol), and
gives 2 when e.g. a->2,b->6
In Mathematica 5 it prints as i(a-b)^(1/2) and gives -2, not 2.
Is this documented, and how is it justified? It screws up a lot of my
programmes.
snip

Apologies - this error only appears when I load a recently revised
Mathematica 5.0 package, which I had made compatible with Mathematica
4.2. It disappears when I Quit[]. I shall report back if I find what I
did wrong.
Roger Beresford.


.

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