Mercurial > matrix-functions
annotate toolbox/cycol.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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8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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1 function A = cycol(n, k) |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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2 %CYCOL Matrix whose columns repeat cyclically. |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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3 % A = CYCOL([M N], K) is an M-by-N matrix of the form A = B(1:M,1:N) |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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4 % where B = [C C C...] and C = RANDN(M, K). Thus A's columns repeat |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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5 % cyclically, and A has rank at most K. K need not divide N. |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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6 % K defaults to ROUND(N/4). |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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7 % CYCOL(N, K), where N is a scalar, is the same as CYCOL([N N], K). |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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8 % |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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9 % This type of matrix can lead to underflow problems for Gaussian |
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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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10 % elimination: see NA Digest Volume 89, Issue 3 (January 22, 1989). |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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11 |
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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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12 m = n(1); % Parameter n specifies dimension: m-by-n. |
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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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13 n = n(max(size(n))); |
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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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14 |
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Antonio Pino Robles <data.script93@gmail.com>
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15 if nargin < 2, k = max(round(n/4),1); end |
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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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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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17 A = randn(m, k); |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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18 for i=2:ceil(n/k) |
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Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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19 A = [A A(:,1:k)]; |
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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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20 end |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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21 |
8f23314345f4
Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
parents:
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22 A = A(:, 1:n); |