[IAEP] Working math graphs/plots

[Reinier Heeres]

Hi,

I agree that the plotting functionality is not really well exposed, 
although help(index) will show you it's available and help(plot) will 
tell you how to use it. Try plot(sin(x),x=0..360) for example. I'll work 
on the exposure of plotting in the next release; suggestions on how to 
do this exactly would be welcome.

The implementation is as basic as it can get: it evaluates an expression 
at 100 points between the start and stop range. The internal parser is a 
bit slow, but it's pure python and works reasonably well.

With a bit of coding we could surely add some functionality to get data 
from Measure in there too.

I am not inclined to add RPN parsing myself, but patches will of course 
be considered.

Regards,
Reinier

Edward Cherlin wrote:
> On Wed, Dec 10, 2008 at 11:18 AM, Gary C Martin <gary at garycmartin.com> wrote:
>   
>> On 10 Dec 2008, at 18:41, Walter Bender wrote:
>>
>>     
>>> I haven't looked at it in a while, but what plotting engine is built
>>> inside of the Calculator Activity?
>>>
>>> -walter
>>>       
>> I think Reinier wrote his own little svg plot generator class called
>> plotlib.py.
>>
>> --Gary
>>     
>
> I didn't know about the plotting capability, which will have endless
> uses. It is certainly not discoverable.
>
> Can we feed a segment of a data stream from Measure to Calculate as a
> named function?
>
> Why don't we put something like plot(f(x),x=min..max) on the toolbar?
> Can we provide hints about the functions and syntax anywhere in the
> UI? Is there a way to recall and edit an input line? Are there other
> functions not exposed in the UI?
>
> I have a fairly old book called Numerical Analysis on the Pocket
> Calculator, which explains how to do all sorts of things that you
> might not expect on even the simplest 4- and 5-function devices, and
> works on up through the sort of algebraic calculator we have here to
> the programmable calculator. Our users will need something like this,
> to take maximum advantage of the seemingly limited capabilities we are
> offering them.
>
> And can we have an RPN mode? I can't tell you how much most real
> engineers hate parentheses. We are not doing children any favors by
> hiding the more advanced tools.
>   

-- 
Reinier Heeres
Waalstraat 17
2515 XK Den Haag
The Netherlands

Tel: +31 6 10852639