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annotate toolbox/vand.m @ 0:8f23314345f4 draft
Create local repository for matrix toolboxes. Step #0 done.
author | Antonio Pino Robles <data.script93@gmail.com> |
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date | Wed, 06 May 2015 14:56:53 +0200 |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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1 function V = vand(m, p) |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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2 %VAND Vandermonde matrix. |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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3 % V = VAND(P), where P is a vector, produces the (primal) |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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4 % Vandermonde matrix based on the points P, i.e. V(i,j) = P(j)^(i-1). |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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5 % VAND(M,P) is a rectangular version of VAND(P) with M rows. |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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6 % Special case: If P is a scalar then P equally spaced points on [0,1] |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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7 % are used. |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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8 |
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Antonio Pino Robles <data.script93@gmail.com>
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9 % Reference: |
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10 % N.J. Higham, Stability analysis of algorithms for solving |
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Antonio Pino Robles <data.script93@gmail.com>
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11 % confluent Vandermonde-like systems, SIAM J. Matrix Anal. Appl., |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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12 % 11 (1990), pp. 23-41. |
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Create local repository for matrix toolboxes. Step #0 done.
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13 |
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14 if nargin == 1, p = m; end |
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Antonio Pino Robles <data.script93@gmail.com>
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15 n = max(size(p)); |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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16 |
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17 % Handle scalar p. |
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18 if n == 1 |
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19 n = p; |
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20 p = seqa(0,1,n); |
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21 end |
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22 |
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23 if nargin == 1, m = n; end |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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24 |
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25 p = p(:).'; % Ensure p is a row vector. |
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Create local repository for matrix toolboxes. Step #0 done.
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26 V = ones(m,n); |
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27 for i=2:m |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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28 V(i,:) = p.*V(i-1,:); |
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Create local repository for matrix toolboxes. Step #0 done.
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29 end |