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

["V. Armando Solé"]

I forgot to add that *perhaps* is simpler to embed a Python interpreter 
in C or C++ (and then you are done a lot of functions) than to wrap/add 
muParser for just one functionality.

On 14/03/2014 15:08, "V. Armando Solé" wrote:
> 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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>>>
>>
>>
>>
>
>
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