But for calculating eps inside get_fargs function like in fibre_function:

 eps =  nm.zeros_like(mat1)
        omega = nm.empty_like(green_strain)
        for ii, (ir, ic) in enumerate(iter_sym(fdir.shape[2])):
            omega[..., ii, 0] = fdir[..., ir, 0] * fdir[..., ic, 0]
            eps[..., 0, 0] += omega[..., ii, 0] * green_strain[..., ii, 0]
I would need also as a input argument "green_strain"? 

And then return both, fargs and deps not?:

"return deps, fargs"

Sorry for the amount of silly questions, I am very new using Python and finite-element modeling :)

El viernes, 23 de octubre de 2015, 10:39:07 (UTC+2), Patricia Garcia Cañadilla escribió:
Dear Robert,

I would like to the model the viscoelastic behavior of active fibers, as you done in the paper: "Modelling heart tissue using a composite muscle model with blood perfusion" or as here: http://citeseerx.ist.psu.edu/viewdoc/download?doi= and I was wondering if is easy to implemented in sfepy and/or if there is some predefined term in Sfepy, since for example the term "dw_tl_fib_a" doesn't include the "exp{k min(0;de/dt}}" that appears in the paper.

Thank you very much for your help :)