[firedrake] Problem with Jacobian

[Buesing, Henrik]

Dear all,

I'm having a variable Sw, which I calculate pointwise in a routine calc_Sw (see attachment). This variable depends on my primary unknown h: Sw = (h-hn)/(hw-hn) (hn,hw known values).

But now it seems like automatic differentiation for this routine does not work. I'm getting zero entries for the Jacobian, whereas d(Sw)/dh = 1.0 should hold.

Do I have to write this routine with conditionals? I tried this, but failed. How would my routine calc_Sw have to look like with conditionals?

Thank you!

Henrik


--
Dipl.-Math. Henrik Büsing
Institute for Applied Geophysics and Geothermal Energy
E.ON Energy Research Center
RWTH Aachen University
------------------------------------------------------
Mathieustr. 10            |    Tel +49 (0)241 80 49907
52074 Aachen, Germany     |    Fax +49 (0)241 80 49889
------------------------------------------------------
http://www.eonerc.rwth-aachen.de/GGE
hbuesing at eonerc.rwth-aachen.de
------------------------------------------------------

-------------- next part --------------
HTML attachment scrubbed and removed
-------------- next part --------------
A non-text attachment was scrubbed...
Name: saturation.py
Type: application/octet-stream
Size: 504 bytes
Desc: saturation.py
URL: <http://mailman.ic.ac.uk/pipermail/firedrake/attachments/20151105/c777b965/attachment.obj>