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Re: General pow(xx,yy) function in Motion 10

Michel Hack wrote:

Nate Hayes wrote:

With the general power function, however, the width of the interval
range
zz will always be at least the distance between the two manifolds
for any negative xx.  This distance is quite large and will most
likely be much larger than the user's tolerance criteria for the
branch and bound algorithm.


What would be the meaning of an interval xx that includes relatively
large negative values, when raised to an uncertain real exponent?
I don't really think it makes sense, either. It's another reason that I'm skeptical of the general power function; and why I was hoping someone could provide an example of why it is required.
Since it was listed as required in Motion 10, I was assuming some of our experts in the forum saw this as being important. I was just looking at the consequences of what happens when you put it into a branch-and-bound algorithm. That's all. 

Personally, I like Arnold's suggestions:


Thus I recommend making integral powers and nonnegative real powers
mandatory, and the most general power and the rational power optional.


Nate