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标题:
Matlab之用牛顿均差求插值多项式
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作者:
haidaowang
时间:
2020-8-27 13:55
标题:
Matlab之用牛顿均差求插值多项式
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% 写出一个插值多项式
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% input :vector(x,y),interpolation point x0
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% output:the result at x = x0
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function y0 = page_157_1(x ,y,x0)
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format long
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n = length(x);
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for j = 1:n %fill in y colum of Newton triangle
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v(j,1) = y(j);
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end
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for i = 2:n %for colum i
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for j = 1:n+1-i %fill in colum from top to bottom
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v(j,i) = (v(j+1,i-1) - v(j,i-1))/(x(j+i-1)-x(j));
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end
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end
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for i = 1:n
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v(i) = v(1,i); %read along top of triangle
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end %output coefficients
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y0 = v(n)*(x0 - x(n-1)) + v(n-1); %initial nest
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for i = 1:n-2 %use nest
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y0 = y0*(x0 - x(n-1-i)) + v(n-1-i);
% |* E, ^# [8 |; I
end
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作者:
youOK
时间:
2020-8-27 14:43
Matlab之用牛顿均差求插值多项式
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