You can use the Python Calculator, which will let you use any valid Python expression -- such as math.atan2().
Tim ----- Original Message ----- From: "Nico Schlömer" <nico.schloe...@gmail.com> To: "Andy Bauer" <andy.ba...@kitware.com> Cc: paraview@paraview.org Sent: Wednesday, February 16, 2011 8:29:02 AM Subject: Re: [Paraview] unstructured grid, programmable filters: extract, process array data Almost there! > atan(coordsX/coordsY) If instead of coordsX I use psi__{X,Y}, things work. However, I need something slightly different than atan: I'd like to get the complex argument of a complex number X+iY (i.e., the angle with the positive real axis). It's quite ~similar~ to what atan does, see for example <http://gcc.gnu.org/onlinedocs/gcc-4.0.4/gfortran/ATAN2.html>. In Python, the function is called math.atan2() as well. ParaView's calculator filter does however not support atan2(), and that was my original motivation to look at programmable filters actually. Well, it'd be much nicer if the same thing could be done with the calculator of course! Workarounds? --Nico On Tue, Feb 15, 2011 at 6:56 PM, Andy Bauer <andy.ba...@kitware.com> wrote: > This sounds like a job for the calculator filter. "coordsX^2+coordsY^2" for > your first example (or "psi__X^2+psi__Y^2" for the psi variables) and > "atan(coordsX/coordsY)" for the second example. > > It can operate on point or cell data (set in the Attribute Model drop-down > menu), replace invalid numbers with a specified value, and you can name the > resulting array as well. > > Andy > > 2011/2/15 Nico Schlömer <nico.schloe...@gmail.com> >> >> Hi all, >> >> I've been looking at >> <http://www.paraview.org/Wiki/Python_Programmable_Filter> to create a >> programmable filter, but I'm a bit lost as to whether or not I need >> GetPolyData, CopyAttributes,... >> >> Essentially, I have an unstructured grid in an ExodusII file (like the >> attached file actually) with point data "psi" in it that has two >> components (X,Y). I can plot psi:X, psi:Y, and psi:magnitude alright >> with the default GUI options, but what I would really like to have >> plotted is X^2+Y^2 (no sqrt()) and something along the lines of >> arctan(Y/X). >> >> Is there simple code somewhere some that takes array data off of an >> unstructured grid, does something with it and returns the extra array >> from the filter? >> >> Cheers, >> Nico >> >> _______________________________________________ >> Powered by www.kitware.com >> >> Visit other Kitware open-source projects at >> http://www.kitware.com/opensource/opensource.html >> >> Please keep messages on-topic and check the ParaView Wiki at: >> http://paraview.org/Wiki/ParaView >> >> Follow this link to subscribe/unsubscribe: >> http://www.paraview.org/mailman/listinfo/paraview >> > > _______________________________________________ Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview _______________________________________________ Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Follow this link to subscribe/unsubscribe: http://www.paraview.org/mailman/listinfo/paraview