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Re: motion elementary functions



Hossam
  thanks for the comments. I'll put the changed motion on the website
Juergen

Hossam A. H. Fahmy schrieb:
Jurgen and P1788,

I noticed a few typos in the proposed motion:

For root, the domain should be [0,oo)xZ
I changed the function name to rootn and allowed for negative x as well

For rSqrt, the domain should be (0,oo) , with the zero excluded
yes

For compound, the domain should be (-1, oo)xZ with the one excluded due to cases of negative powers which lead to division by zero, otherwise, you can make it [-1,oo)xN
No I prefer an exception for X=1 n<0

For logp1, the domain should be (-1, oo) with the one excluded.
yes

For all the functions in table 2 that have a division by x we must exclude zero obviously.
yes

For pow, I prefer that we allow the full domain of RxR. For me, pow is the most general form of sqr, pown, sqrt, powr, root, rSqrt, and compound. Hence, I think that we should not prevent someone who wants to calculate (-32)^(0.2)=-2 from doing just that in a simple fashion as pow(-32,0.2).
I don't like this. The user should call rootn(-32,5)
see rationale

Hope this is useful.
--
Hossam A. H. Fahmy
Assistant Professor
Electronics and Communications Department
Cairo University
Egypt


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