comparison toolbox/vand.m @ 2:c124219d7bfa draft

Re-add the 1995 toolbox after noticing the statement in the ~higham/mctoolbox/ webpage.
author Antonio Pino Robles <data.script93@gmail.com>
date Thu, 07 May 2015 18:36:24 +0200
parents 8f23314345f4
children
comparison
equal deleted inserted replaced
1:e471a92d17be 2:c124219d7bfa
1 function V = vand(m, p)
2 %VAND Vandermonde matrix.
3 % V = VAND(P), where P is a vector, produces the (primal)
4 % Vandermonde matrix based on the points P, i.e. V(i,j) = P(j)^(i-1).
5 % VAND(M,P) is a rectangular version of VAND(P) with M rows.
6 % Special case: If P is a scalar then P equally spaced points on [0,1]
7 % are used.
8
9 % Reference:
10 % N.J. Higham, Stability analysis of algorithms for solving
11 % confluent Vandermonde-like systems, SIAM J. Matrix Anal. Appl.,
12 % 11 (1990), pp. 23-41.
13
14 if nargin == 1, p = m; end
15 n = max(size(p));
16
17 % Handle scalar p.
18 if n == 1
19 n = p;
20 p = seqa(0,1,n);
21 end
22
23 if nargin == 1, m = n; end
24
25 p = p(:).'; % Ensure p is a row vector.
26 V = ones(m,n);
27 for i=2:m
28 V(i,:) = p.*V(i-1,:);
29 end