Possible to "expand" function handle?
3 次查看(过去 30 天)
显示 更早的评论
I've written a function that returns a function handle to a Lagrange polynomial L(x):
function L = lagrange(xv,yv)
% make sure xv and yv are row vectors
xv = xv(:);
yv = yv(:);
% check for equal dimensions
if size(xv) ~= size(yv)
error('xv and yv must be of same dimensions');
end
% number of points
n = length(xv);
% initialize to zero
L = @(x)0;
for k = 1:n
l = @(x)1; % initialize k'th basis polynomial
for m = 1:n
if k ~= m % if k different from m, calculate basis
l = @(x)(l(x).*(x-xv(m))/(xv(k)-xv(m)));
end
end
L = @(x)(L(x)+yv(k).*l(x)); % perform linear combination
end
It seems to work as I want it to (calling L(4), or whatever, produces the correct result), but if I type L in the command line, Matlab prints "L = @(x)(L(x)+yv(k).*l(x))".
Is it possible to get the complete function printed out? I.e., if my yv vector stems from the function x^3, then the Lagrange polynomial should be 6x^2-11x+6, but I can't figure out how to get this printed out; is it posible?
best regards
dm
0 个评论
采纳的回答
更多回答(0 个)
另请参阅
类别
在 Help Center 和 File Exchange 中查找有关 Polynomials 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!