14 replies to this topic

[Orwell]

Actually it should return a CAS expression with value "345678/10000"... It works correctly on my CP

[Orwell]

There is no function to do that yet
But don't worry it will be available in the next releases

Edited by Orwell, 11 November 2005 - 11:48 AM.

[PAP]

Orwell, on Nov 11 2005, 02:44 PM, said:

There is no function to do that yet
But don't worry it will be available in the next releases

Hmmm, Orwell it seems that you are quite busy indeed. You can convert a CAS result to a numerical value by treating it as a CAS function:

foo=cas.fround(34.567831,3)

makes foo a "userdata" variable equal to 172839/5000, but

foo(0)

is a "number" variable equal to 34.5678. You can even assign that variable to foo directly:

foo=cas.fround(34.567831,3)(0)

will make foo a number variable.
In general, if foo is a CAS numerical result, it can be converted to a CPLua "number" variable by issuing foo(any number). It seems that this is a side-effect of the way that CAS functions can be used in CPLua, but it works, provided that the CAS result is not in exponential form (see my bug report for that).

[Orwell]

That's right, I didn't think about that actually
But I think that something like 'cas.tonumber' or 'cas.evaluate' would be better

[PAP]

Orwell, on Nov 11 2005, 08:15 PM, said:

But I think that something like 'cas.tonumber' or 'cas.evaluate' would be better

Indeed, such a function will make things much clearer. "cas.evaluate" seems a very good name for this function. If I remeber well, Kilburn asked something similar to Tom's question a few days ago. It is currently not clear to most CPLua users that <CAS expression>(0) does the right thing.
However, the current way to evaluate a CAS expression works, and I extensively use it in the project I'm working these days. If you are planning to change the current behavior, let me know...

[PAP]

Tom, on Nov 12 2005, 03:20 PM, said:

Tihis is it!! Thank You!!!

Solving CPLua programming problems is always a pleasure.

[Orwell]

Cool, now I can introduce any bug I want since it will be a pleasure to solve them

[PAP]

Orwell, on Nov 12 2005, 08:18 PM, said:

Cool, now I can introduce any bug I want since it will be a pleasure to solve them

Nooo, I didn't said that solving bugs is a pleasure. I said that I like solving programming problems, not bugs . Thanks for your "offer", but I don't want more bugs...

[Orwell]

In the next CPLua version it will be possible to evaluate CAS expressions (to convert them into a simple number) in the same way, but without having to give a fake "zero" value in the parenthesis.
Thus,

x = cas("45/7")
x2 = x()

will create a number 'x2' with value 6.428...

[PAP]

Orwell, on Nov 16 2005, 09:51 PM, said:

In the next CPLua version it will be possible to evaluate CAS expressions (to convert them into a simple number) in the same way, but without having to give a fake "zero" value in the parenthesis.
Thus,

x = cas("45/7")
x2 = x()

will create a number 'x2' with value 6.428...

Short, clear, functional. I like it. But what if you add a fake number anyway? For example, if you forgot to remove a zero (or any other number), needed in previous versions?

[Orwell]

The result will be the same than in previous versions, so this will be accepted too