[Nexus] proposed additions to NXdata for non-linear scaling - to aid cbf interoperability

["V. Armando Solé"]

Here is my proposal (I have something similar somewhere else)

Group @NXformula
formula (string where parameters are denoted by {i} with i=1, ...., n. 
The idea is to be able to replace {i} by x_i)
x_1  (dataset)
x_2 (dataset)
x_3 (dataset)
....
x_n (dataset)

Where we could disagree is that for formula validity I would take any 
expression that can be evaluated by Python once {i} has been replaced by x_i

I guess you could just decide that the expression resulting from 
replacing {i} by x_i should be a valid muParser expression.

The nice thing about Python would be that the expression could be used 
to apply a transformation on element by element of each referenced 
dataset or  to be applied as a whole to the dataset. I do not know if it 
is the case with muParser.

Armando


On 13/03/2014 15:25, yayahjb wrote:
> Having python, or something equivalent, available is a nice 
> convenience and a good, portable
> way to document the algorithms that are used in many setups. 
> Performance way well dictate
> using hand-tooled C or C++ code in practice, but that higher 
> performance code is more likely
> to be right with a python or similar example available.  Think of it 
> as particularly effective
> documentation.
>
> Regards,
>     Herbert
>
> On 3/13/14 9:00 AM, "V. Armando Solé" wrote:
>> On 19/02/2014 14:28, Mark Koennecke wrote:
>>> Hi,
>>>
>>>
>>> On 02/19/2014 11:15 AM, Wintersberger, Eugen wrote:
>>>> Hi folks
>>>>
>>>> On Wed, 2014-02-19 at 10:11 +0100, Benjamin Watts wrote:
>>>>> Hi Jonathan,
>>>>>      This kind of thing has been discussed at previous NIAC meetings.
>>>> At the end of the day there is one question we should seriously 
>>>> discuss:
>>>> how far do we want to go with math in Nexus?
>>> This is exactly the point why we never got down to anything in this.
>>> In 2011, Amando was tasked to make a proposal but nothing ever
>>> came from it. 
>>
>> I thought it was agreed at the NIAC meeting in OakRidge to use muParser.
>>
>> If a proposal would come from me it would certainly be Python based :-)
>>
>> Armando
>>
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>
>
>