function [V,d] = InvIteration(K,M,epslon)
%    [V,d]=InvIteration（K,M）
%    k * V=d * M * V
%输入参数
%    K,M----维数相同的方阵
%    epslon--计算要求的精度
%  返回值
%    V----特征向量
%    d----特征值

ys = diag(M);
s = 0;
while 1
    s = s+1;
    xs1 = Kys;
    ys1 = M*xs1;
    if s == 1
        ros = transpose(xs1)*ys/(transpose(xs1)*ys1);
    else
        ros1 = transpose(xs1)*ys/(transpose(xs1)*ys1);
        if abs(ros1-ros)/ros1 <= epslon
            break;
        else
            ros = ros1;
        end
    end
    ys = ys1 / (transpose(xs1)*ys1)^(1/2);
end
d=ros1;
V=xs1/(transpose(xs1)*ys1)^(1/2);
return