# ekey

Specify the method used to determine the error tolerance in the solve-estimate-refine iterations of the finite element solver (fe-manual). The syntax is:

    ekey { flag }

where `flag` is a text string that determines the method for error calculation.

`simp`
  Per-simplex error limit
`global`
  Global (whole domain) error limit
`frac`
  Fraction of simplices you’d like to see refined at each iteration