Mercurial > hg > ltpda

comparison m-toolbox/classes/+utils/@math/welchscale.m @ 43:bc767aaa99a8

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
CVS Update
author Daniele Nicolodi <nicolodi@science.unitn.it>
date Tue, 06 Dec 2011 11:09:25 +0100
parents
children
comparison
equal deleted inserted replaced
0:f0afece42f48 43:bc767aaa99a8
1 % WELCHSCALE scales the output of welch to be in the required units
2 %
3 % $Id: welchscale.m,v 1.1 2011/12/01 09:41:22 hewitson Exp $
4 %
5
6 function [yy, dyy, info] = welchscale(xx, dxx, win, fs, norm, inunits)
7
8 nfft = length(win);
9 S1 = sum(win);
10 S2 = sum(win.^2);
11 enbw = fs * S2 / (S1*S1);
12
13 if isempty(norm)
14 norm = 'None';
15 end
16 switch lower(norm)
17 case 'asd'
18 yy = sqrt(xx);
19 if isempty(dxx)
20 dyy = dxx;
21 else
22 dyy = 1./2./sqrt(xx) .* dxx;
23 end
24 info.units = inunits ./ unit('Hz^0.5');
25 case 'psd'
26 yy = xx;
27 dyy = dxx;
28 info.units = inunits.^2/unit('Hz');
29 case 'as'
30 yy = sqrt(xx * enbw);
31 if isempty(dxx)
32 dyy = dxx;
33 else
34 dyy = 1./2./sqrt(xx) .* dxx * enbw;
35 end
36 info.units = inunits;
37 case 'ps'
38 yy = xx * enbw;
39 dyy = dxx * enbw;
40 info.units = inunits.^2;
41 case 'none'
42 yy = xx;
43 dyy = dxx;
44 info.units = inunits;
45 otherwise
46 error('Unknown normalisation');
47 end
48
49 info.nfft = nfft;
50 info.enbw = enbw;
51 info.norm = norm;
52
53 end
54