Garth N. Wells wrote:
> I don't know if Nedelec elements have been tested with FFC. Start with 
> something simpler.
>
>   

They've been tested.

--
Marie


> Garth
>
> Evan Lezar wrote:
>   
>> Hi there
>>
>> I have implemented a simple test case and have attached it.  In writing 
>> it, I made a discovery.  The vector that is passed as a list of 
>> coefficients to the function constructor (h_e in the example) needs to 
>> be a multidimensional array with the first dimension 1.  If one swaps 
>> the dimensions (1, num_dofs) on line 26, then the test crashes when 
>> field.eval is called.
>>
>> However, according to me, the eval function does not work as expected.  
>> Since the list of coefficients is zero and the function should be 
>> evaluated as the weighted sum of the basis functions using the 
>> coefficients as weights, this means that the function value returned for 
>> any position within the mesh should be zero.  However, the first 
>> component (let us say x) of H is always -1 and the second component is 
>> not changed and retains the value that was assigned to it before the 
>> call to evaluate.
>>
>> I will see about getting a C++ test up and running to test the same thing.
>>
>> Please let me know if there are any other questions.
>> Evan
>>
>> On Thu, Aug 21, 2008 at 6:06 PM, Evan Lezar <[EMAIL PROTECTED] 
>> <mailto:[EMAIL PROTECTED]>> wrote:
>>
>>
>>
>>     On Thu, Aug 21, 2008 at 5:49 PM, Ola Skavhaug <[EMAIL PROTECTED]
>>     <mailto:[EMAIL PROTECTED]>> wrote:
>>
>>         Evan Lezar skrev den 21/08-2008 følgende:
>>          > Thanks for the speedy replies from all of you.
>>          >
>>          > Firstly platform information
>>          >
>>          > I am running ubuntu hardy, gcc version 4.2.3, swig 1.3.33,
>>         python 2.5 with
>>          > release versions of numpy and scipy.  I am building dolfin
>>         directly from
>>          > source with mpi, but have not enabled petsc or any of the
>>         other optional
>>          > packages.
>>          >
>>          > What other information do you require?
>>          >
>>          > In terms of my specific problem, see the following code snippet:
>>          >
>>          > from dolfin import *
>>          > import numpy as N
>>          >
>>          > mesh = UnitSquare(4,4)
>>          > element = FiniteElement("Nedelec", "triangle", 0)
>>          >
>>          > ### Code to assemble system matrices and solve an eigenvalue
>>         problem
>>          >
>>          > # h_e is an array of coefficients associated with the degrees
>>         of freedom in
>>          > the system obtained from the eigenvectors V
>>          > h_e = V[:,sorted_index[first_index]]
>>          >
>>          > # setup a function to evaluate - the solution of the magnetic
>>         field
>>          > field = Function(element, self.mesh, h_e)
>>          >
>>          > # arbitrary point to evaluate the field
>>          > points = N.array((0.5,0.25))
>>          > # array to store the field value at a point
>>          > H = N.array((0.0,0.0))
>>          >
>>          > print "pre_eval"
>>          >
>>          > #evaluate the function
>>          > field.eval(H, points)
>>          >
>>          > # Ouput the field at the point
>>          > print "H",
>>          > print H
>>          >
>>          >
>>          > When I run this code, I get the following output:
>>          >
>>          > pre_eval
>>          > [labby:25160] *** Process received signal ***
>>          > [labby:25160] Signal: Segmentation fault (11)
>>          > [labby:25160] Signal code: Address not mapped (1)
>>          > [labby:25160] Failing at address: 0xde8f58ec
>>          > [labby:25160] [ 0] [0xb7f81440]
>>          > [labby:25160] [ 1] /usr/bin/python(PyEval_EvalCodeEx+0x6e7)
>>         [0x80cb0d7]
>>          > [labby:25160] [ 2] /usr/bin/python(PyEval_EvalFrameEx+0x565e)
>>         [0x80c92de]
>>          > [labby:25160] [ 3] /usr/bin/python(PyEval_EvalCodeEx+0x6e7)
>>         [0x80cb0d7]
>>          > [labby:25160] [ 4] /usr/bin/python(PyEval_EvalFrameEx+0x565e)
>>         [0x80c92de]
>>          > [labby:25160] [ 5] /usr/bin/python(PyEval_EvalCodeEx+0x6e7)
>>         [0x80cb0d7]
>>          > [labby:25160] [ 6] /usr/bin/python(PyEval_EvalCode+0x57)
>>         [0x80cb227]
>>          > [labby:25160] [ 7] /usr/bin/python(PyRun_FileExFlags+0xf8)
>>         [0x80ea6d8]
>>          > [labby:25160] [ 8] /usr/bin/python(PyRun_SimpleFileExFlags+0x199)
>>          > [0x80ea979]
>>          > [labby:25160] [ 9] /usr/bin/python(Py_Main+0xa35) [0x8059335]
>>          > [labby:25160] [10] /usr/bin/python(main+0x22) [0x80587f2]
>>          > [labby:25160] [11]
>>         /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe0)
>>          > [0xb7de8450]
>>          > [labby:25160] [12] /usr/bin/python [0x8058761]
>>          > [labby:25160] *** End of error message ***
>>          >
>>          > With a previous build I have gotten different output and was
>>         able to
>>          > actually display the contents of H, but it would shill crash
>>         once the method
>>          > where the code was being run was terminated.  I logged a bug
>>         against it at
>>          > http://www.fenics.org/cgi-bin/bugzilla/show_bug.cgi?id=55
>>          >
>>          > As I said in my mail, I see myself using fenics in the long
>>         run and would
>>          > like to get involved as much as possible, but some pointers
>>         as to where to
>>          > start would be much apprciated.
>>
>>         Have you implemented the C++ version as well, such that you know
>>         that what you
>>         do is correct? 
>>
>>
>>         Clearly, we are not catching what's going wrong here (missing
>>         check of some
>>         sort).
>>
>>         My guess is that the error occurs in
>>         site-packages/dolfin/function.py, when
>>         the Function is initialized. Can you boil down the example to a
>>         shorter script
>>         and post it to this list? I'll have a look at it.
>>
>>         Ola
>>
>>
>>     Hi
>>
>>     I have not implemented a C++ version, but I will look into it - I am
>>     a little more comfortable with python at the moment, but I suppose I
>>     need to jump into the deep end :)
>>
>>     I will write a simple example script and then attach that.
>>
>>     Evan
>>
>>
>>
>> ------------------------------------------------------------------------
>>
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>
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>   


-- 
Marie E. Rognes
Ph.D Fellow, 
Centre of Mathematics for Applications, 
University of Oslo
http://folk.uio.no/meg

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