function [cc] = calcoef(T, y)
    exec('**/cald.sci', -1)

    n = size(y, 1)
    cc = zeros(n-1, n-1)
    d = zeros(n, 1)
    h = zeros(n-1, 1)
    h2 = zeros(n-1, 1)
    h3 = zeros(n-1, 1)
    l = zeros(n-1, 1)
    
    d = cald(T, y)
    h = T(2:n) - T(1:n-1)
    h2 = h.*h
    h3 = h.*h.*h
    l = y(2:n) - y(1:n-1)
    
    cc(:, 1) = y(1:n-1)
    cc(:, 2) = d(1:n-1)
    cc(:, 3) = l./h2 - d(1:n-1)./h
    cc(:, 4) = (d(2:n) - d(1:n-1))./h2 - 2 * l./h3
    
endfunction