Kurt Pagani wrote:
>
> It's not easy to grasp when looking at the sequence below. I've tried to
> trace "atan" in the code but there are really weird ramifications.
>
>
> (2) ->
> atan((x^2*((-1)*x^4+1)^(1/2)+(x^3+x))/(((-1)*x^4+1)^(1/2)+((-1)*x^3+x)))
>
> +--------+
> 2 | 4 3
> x \|- x + 1 + x + x
> (2) atan(----------------------)
> +--------+
> | 4 3
> \|- x + 1 - x + x
> Type: Expression(Integer)
> (3) -> atan(x*(1 + x^2)/sqrt(1 - x^4))
>
> +--------+
> 2 | 4 3
> x \|- x + 1 + x + x
> (3) atan(----------------------)
> +--------+
> | 4 3
> \|- x + 1 - x + x
> Type: Expression(Integer)
> (4) -> atan(y*(1 + y^2)/sqrt(1 - y^4))
>
> 3
> y + y
> (4) atan(-----------)
> +--------+
> | 4
> \|- y + 1
> Type: Expression(Integer)
> (5) -> atan(x*(1 + x^2)/sqrt(1 - x^4))
>
> 3
> x + x
> (5) atan(-----------)
> +--------+
> | 4
> \|- x + 1
> Type: Expression(Integer)
This is a bug. We can avoid this bug by using:
setSimplifyDenomsFlag(true)
but then different bugs in other places show up. This bug
is due to use of linear order in Kernel. In principle we
could avoid it by avoid linear order (using linear search
instead of binary search), but then Kernel would became
very slow.
--
Waldek Hebisch
--
You received this message because you are subscribed to the Google Groups
"FriCAS - computer algebra system" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/fricas-devel.
For more options, visit https://groups.google.com/d/optout.
