Performs a Zienkiewicz-Zhu type error estimator.
numproc zzerrorestimator ee1 -bilinearform=a -solution=u -error=err
Averages the fluxes, and computes difference between averaged flux and original flux. Difference is added to element by element gridfunction error. Averaging is done sub-domain by sub-domain to avoid too strong refinement along material interfaces.
|-bilinearform=<name>||first integrator of bilinear-form defines flux|
|-solution=<name>||gridfunction containing solution|
|-error=<name>||element-by-element, order 0 gridfunction containing element contributions of error|