function h = krw_gw(sw, SW, KRW, varargin)
n = numel(varargin);
if n == 0
    h = interptable(SW, KRW, sw);
else
    SWF = varargin{1};
    KRWF = varargin{2};
    rpt = varargin{3};
    hm = interptable(SW, KRW, sw);
    hf = interptable(SWF, KRWF, sw);
    h = rpt .* hm + ~rpt .* hf;
end
% h=sw-sw;
end