problem with Gauss Hermite ( x and w )

Hello,

Negative powers mean they take the reciprocal and as far as I am
concerned, real^real is just a real number.
Am I mistaking something basic?

Yes, you are.

real^real is not necessarily real.

The most well known example is (-1)^0.5 = imaginary unit.
When you say that -2.5^(-2.4) is real you're computing the negative power of
a POSITIVE real, 2.5 then taking the result's  symmetric.

(-2.5)^(-2.4)
[1] NaN

Or
(-1)^0.5
[1] NaN
-1^0.5
[1] -1

(-1 + 0i)^0.5 # algebraically, equal to (-1)^0.5 above, but not in R
notation.
[1] 0+1i

Hope this helps,

Rui Barradas



casperyc wrote

Hi,

 I know what complex number are, but I am not sure what you meant by that?


##############CODES###########

2.5^(-2.4)

[1] 0.1109032

-2.5^(-2.4)

[1] -0.1109032
##############CODES###########

works fine.

Negative powers mean they take the reciprocal and as far as I am
concerned, real^real is just a real number.

Am I mistaking something basic?

Thanks.

Casper

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