program for lagranges interpolation method using single for loop
2 views (last 30 days)
Show older comments
how to program for lagranges interpolation method using single for loop
4 Comments
Geoff Hayes
on 23 Aug 2018
Please rename your local variable sum since it conflicts with the MATLAB built-in function of the same name.
Out of curiosity, why do you want to eliminate the inner for loop? For performance reasons?
Answers (1)
Geoff Hayes
on 23 Aug 2018
PJS - if we assume that x is a vector/array then u is simply
u = (a - x(1)) * (a - x(2)) * ... * (a - x(i-1)) * (a - x(i+1)) * ... * (a - x(n));
where n is the number of elements in x. If this is true, then couldn't we do something like
for i = 1:length(x)
u = 1;
l = 1;
xt = x;
xt(i) = []; % remove the ith element
u = prod(a - xt);
% etc.
end
l = (x(i) - x(1)) * (x(i) - x(2)) * ... * (x(i) - x(i-1)) * (x(i) - x(i+1)) * ... * (ax(i) - x(n));
which means that the above can be replaced with
l = prod(x(i) - xt));
Try the above and see what happens!
0 Comments
See Also
Categories
Find more on Interpolation in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!