假设数据存储在矩阵A中,其中0表示缺失值,则可以使用如下的Matlab代码进行埃米尔特插值:

% 埃米尔特插值函数
function y = hermite_interp(x, y, dy, xi)
n = length(x);
Q = zeros(2*n, 2*n);
Q(1:2:2*n-1, 1) = y;
Q(2:2:2*n, 1) = dy;
for j = 2:2*n
    for i = j:2*n
        Q(i, j) = (Q(i, j-1) - Q(i-1, j-1)) / (x(i) - x(i-j+1));
    end
end
y = zeros(size(xi));
for i = 1:length(xi)
    t = (xi(i) - x(1)) / (x(2) - x(1));
    p = 1;
    for j = 1:2*n-1
        y(i) = y(i) + p * Q(j, j);
        p = p * (t - j/2) / (j+1/2);
    end
end

% 对矩阵A中的0值进行埃米尔特插值
[m, n] = size(A);
for i = 1:n
    % 找到非0值的索引
    idx = find(A(:,i)~=0);
    % 如果所有值都为0,则跳过该列
    if isempty(idx)
        continue;
    end
    % 对非0值进行埃米尔特插值
    x = idx;
    y = A(idx,i);
    dy = zeros(size(y));
    dy(1) = (y(2)-y(1)) / (x(2)-x(1));
    dy(end) = (y(end)-y(end-1)) / (x(end)-x(end-1));
    for j = 2:length(y)-1
        dy(j) = ((y(j+1)-y(j)) / (x(j+1)-x(j)) + (y(j)-y(j-1)) / (x(j)-x(j-1))) / 2;
    end
    xi = find(A(:,i)==0);
    A(xi,i) = hermite_interp(x, y, dy, xi);
end

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