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25
26## -*- texinfo -*-
27## @deftypefn {} {retval =} AbsRel_norm (@var{x}, @var{x_old}, @var{AbsTol}, @var{RelTol}, @var{normcontrol}, @var{y})
28## Undocumented internal function.
29## @end deftypefn
30
31function retval = AbsRel_norm (x, x_old, AbsTol, RelTol, normcontrol, y = zeros (size (x)))
32
33  if (normcontrol)
34    sc = max (AbsTol(:), RelTol * max (sqrt (sumsq (x)), sqrt (sumsq (x_old))));
35    retval = sqrt (sumsq ((x - y))) / sc;
36  else
37    sc = max (AbsTol(:), RelTol .* max (abs (x), abs (x_old)));
38    retval = max (abs (x - y) ./ sc);
39  endif
40
41endfunction
42