Directory: ${PENCIL_HOME}/samples/testfield_xz SVN Id: $Id$ Maintainer: Axel Brandenburg Added: 6-Mar-2013 Status: New reference data since 6 March 2013. Recommended resolution: 32x32x32 with etatest=5e-3 works fine. Comments: This procedure allows the full alpha and eta tensors to be calculated. Different test fields can be used. Note however that the result is in general wavenumber dependent. The present example is for the homogeneous helical turbulence with large-scale uniform shear. IDL> .r p References: Brandenburg, A.: 2005, ``Turbulence and its parametrization in accretion discs,'' Astron. Nachr. 326, 787-797 Brandenburg, A., Radler, K.-H., Rheinhardt, M., & Kapyla, P. J.: 2008, ``Magnetic diffusivity tensor and dynamo effects in rotating and shearing turbulence,'' Astrophys. J. 676, 740-751 Hubbard, A., Rheinhardt, M. & Brandenburg, A.: 2011, ``The fratricide of $\alpha\Omega$ dynamos by their alpha^2 siblings,'' Astron. Astrophys. 535, A48