view +util/matrixborrow.m @ 1016:4b42999874c0 feature/advectionRV

Add lower level for boot-strapping to RungeKuttaExteriorRV - Add a lower level to RungeKuttaExteriorRV for which bootstrapping starts, e.g start bootstrapping from time level 3 using a 3rd order BDF - Clean up ResidualViscosity
author Vidar Stiernström <vidar.stiernstrom@it.uu.se>
date Fri, 07 Dec 2018 13:11:53 +0100
parents 48b6fb693025
children
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function alpha = matrixborrow(A,B)

    function y = neg(x)
        y = min(eig(A-x*B));
    end


    x0 = 1;
    while neg(x0) > -1
        x0 = 2*x0;
    end

    opt = optimset('Display','none');
    alpha = fsolve(@neg, x0,opt);
end