Johan Hake wrote:
> On Thursday 02 July 2009 15:17:08 Garth N. Wells wrote:
>> Johan Hake wrote:
>>> On Thursday 02 July 2009 22:48:18 Marie Rognes wrote:
>>>> Johan Hake wrote:
>>>>> On Thursday 02 July 2009 13:24:28 Garth N. Wells wrote:
>>>>>> Johan Hake wrote:
>>>>>>> On Thursday 02 July 2009 13:07:47 Garth N. Wells wrote:
>>>>>>>> Marie Rognes wrote:
>>>>>>>>> Garth N. Wells wrote:
>>>>>>>>>> Marie Rognes wrote:
>>>>>>>>>>> The following code gives r = 0.0. It is not supposed to be.
>>>>>>>>>>>
>>>>>>>>>>> The problem seems to be that f's vector is still all zeros at the
>>>>>>>>>>> call to interpolate. Could this be easily fixed?
>>>>>>>>>> This example should have led to an error message since f is not a
>>>>>>>>>> discrete function. I'll take a look.
>>>>>>>>> Ok, thanks!
>>>>>>>>>
>>>>>>>>> However,
>>>>>>>>>
>>>>>>>>> (a) Why is f not a discrete function? (It is defined on a finite
>>>>>>>>> element space?)
>>>>>>>> On second thought, it may be a discrete function. I think that this
>>>>>>>> is defined in the Python interface and not the C++ interface, so
>>>>>>>> I'll take a look.
>>>>>>> A user defined function is not a discrete function untill you either
>>>>>>> call interpolate() or vector, also in python. The problem with the
>>>>>>> later is that you then create a vector which is initialized to 0.
>>>>>>>
>>>>>>> I think this has been discussed before, but should we populate the
>>>>>>> vector using f.interpolate() when vector is called on a userdefined
>>>>>>> function?
>>>>>> Or perhaps Function::vector() should throw an error if the vector has
>>>>>> not already been allocated.
>>>>> I vote for this.
>>>>>
>>>>> The error message can include information about the user might want to
>>>>> call interpolate?
>>>> What is wrong with actually populating the vector with the values one
>>>> expects it to have?
>>>> (When would one not want this?)
>>> Nothing is wrong with that. It just changes the state of the userdefined
>>> function. The question is should this change be the implicit result of a
>>> call to Function::vector() or should it be a result of an explicit
>>> action: a call to Function::interpolate().
>>>
>>>> Also note that it is not intuitive to me that one must call
>>>> f.interpolate() before
>>>>
>>>> Pi_f = interpolate(f, Q_h)
>> I thought that I removed the above function from the C++ interface and
>> added
>>
>> Pi_f = interpolate(f)
>
Oops, I meant that I removed
Pi_f.interpolate(f, Q_h)
and added
Pi_f.interpolate(f)
I think that we should remove interpolate.py. It's now a wrapper for
only two lines of code.
Garth
> Marie is refering to the standalone python function interpolate, implemented
> in the interpolate.py file. Not sure what you are aiming at.
>
> I cannot find any non-class interpolate function in c++. At least there are
> no
> such that is wrapped to python.
>
> Johan
>
>> Garth
>>
>>> I agree... Not easy to satisfy every one.
>>>
>>> Should we put in a:
>>>
>>> if not f.has_vector():
>>> info("Interpolating userdefined function.")
>>> f.interpolate()
>>>
>>> in the python part of the interpolate function?
>>>
>>> johan
>
>
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