Symbolics with float - "unapply"

[rag]

Just stumbled over a somewhat nasty effect using symbolics in conjunction with floats.

I know, that whenever you use a float the symbolic evaluation is switched to float and unfortunately there seems to be no way back and no switch/modifier to prevent this happening.

But can anybody explain the follwing effect and what does "unapply.." mean? Was not able to find the message in the help files.

Rag

[ViktorKorobov]

What Mathcad version is used ?

[rag]

Viktor Korobov schrieb:

What Mathcad version is used ?

Sorry! Using Version 14 M030.

[RichardJ]

I see it in MC15 too. It's a bug.

[AWesterman-disa]

Looks like its one of the things that version 12 didn't get wrong!!

[rag]

A Westerman schrieb:

Looks like its one of the things that version 12 didn't get wrong!!

Neither does version 11.

It sure has to do with the "new" symbolic processor MuPad which replaces Maple since version 14.

The "unapply"-message most likely stems from Mupad and Mathcad is simply noncritical displaying.

The function(?) "unapply(4.0,x)(x)" probably is of an internal format which is not understood by Mathcad.

If you copy that expression (you cannot type it in) an try to evaluate it (symbolically), the statement changes(!) to "unapply(4.0,x(x))".

While I understand "apply", my English simply is not good enough to figure out what "unapply" could mean.

Rag

[RichardJ]

As far as I know, "unapply" is not an English word. It's just some internal gobbledygook. Who knows what it means.

[wayne]

1/.4=This is actually a command in Maple,

its on Maples online help.

unapply(expr,x)(x) yields expr

So I guess unapply(4.0,x)(x) is the same as 4.0. Sow what's the problem with that?

said backwords its (x)(x,4.0)ylppanu, which same as 0.4, which makes me feel better because I think of Hawii.

[RichardJ]

So I guess unapply(4.0,x)(x) is the same as 4.0. Sow what's the problem with that?

Darn! That should have been obvious

[mzeftel]

I am logging this for Mathcad 15 future release and Mathcad Prime 2.0.

Thanks,

Mona