author | A.M. Thurnherr <ant@ldeo.columbia.edu> |
Tue, 08 Jul 2014 21:50:22 -0400 | |
changeset 14 | f7f35d9629ab |
parent 0 | 0a450563f904 |
permissions | -rw-r--r-- |
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function y = stdnan(x) |
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% function y = stdnan(x) |
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%STD Standard deviation. |
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% For vectors, STD(x) returns the standard deviation. |
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% For matrices, STD(X) is a row vector containing the |
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% standard deviation of each column. |
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% |
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% STD computes the "sample" standard deviation, that |
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% is, it is normalized by N-1, where N is the sequence |
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% length. |
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% |
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% ignor NaNs |
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% See also COV, MEAN, MEDIAN. |
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|
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% J.N. Little 4-21-85 |
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% Revised 5-9-88 JNL |
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% Copyright (c) 1984-94 by The MathWorks, Inc. |
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|
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|
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[m,n] = size(x); |
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if (m == 1) + (n == 1) |
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x = x(isfinite(x)); |
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m = length(x); |
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if m == 0 |
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y = nan; |
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elseif m == 1 |
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y = 0; |
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else |
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y = norm(x-sum(x)/m) / sqrt(m-1); |
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end |
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else |
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y = zeros(1,n); |
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for i=1:n |
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xi=x(:,i); |
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xi=xi(isfinite(xi)); |
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m=length(xi); |
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if m == 0 |
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y(i) =nan; |
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elseif m == 1 |
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y(i) =0; |
0a450563f904
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parents:
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else |
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avg = sum(xi)/m; |
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y(i) = norm(xi-avg) / sqrt(m-1); |
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end |
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end |
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end |