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Discrete prolate spheroidal sequences (Slepian sequences).
Syntax
[e,v] = dpss(n,nw)
[e,v] = dpss(n,nw,k)
[e,v] = dpss(n,nw,[k1 k2])
[e,v] = dpss(n,nw,'spline')
[e,v] = dpss(n,nw,'spline',Ni)
[e,v] = dpss(n,nw,'linear')
[e,v] = dpss(n,nw,'linear',Ni)
[e,v] = dpss(...,'trace')
[e,v] = dpss(...,'int','trace')
Description
[e,v] = dpss(n,nw)
generates the first 2*nw discrete prolate spheroidal sequences (DPSS) of length n in the columns of e, and their corresponding concentrations in vector v. They are also generated in the DPSS MAT-file database dpss.mat. nw must be less than n/2.
[e,v] = dpss(n,nw,k)
returns the k most band-limited sequences of the 2*nw discrete prolate spheroidal sequences calculated. k must be between 0 and 2*nw.
[e,v] = dpss(n,nw,[k1 k2])
returns the k1-th through the k2-th sequences from the 2*nw discrete prolate spheroidal sequences calculated, where 1 
k1 k2 (2*nw).
For all of the above forms,
|
| (2
W), where W = nw/n is the half-bandwidth and is in radians.
e(:,1) is the length n signal most concentrated in the frequency band || (2W) radians, e(:,2) is the signal orthogonal to e(:,1) that is most concentrated in this band, e(:,3) is the signal orthogonal to both e(:,1) and e(:,2) that is most concentrated in this band, etc.
nw are 2, 5/2, 3, 7/2, or 4.
[e,v] = dpss(n,nw,'spline')
uses spline interpolation to compute e and v from the sequences in dpss.mat with length closest to n.
[e,v] = dpss(n,nw,'spline',Ni)
interpolates from existing length Ni sequences.
[e,v] = dpss(n,nw,'linear')
and
[e,v] = dpss(n,nw,'linear',Ni)
use linear interpolation, which is much faster but less accurate than spline interpolation. 'linear' requires Ni > n.
[e,v] = dpss(...,'trace')
and
[e,v] = dpss(...,'int','trace')
use a trailing 'trace' argument to find out which method DPSS uses, where 'int' is either 'spline' or 'linear'.
See Also
dpssclear |
Remove discrete prolate spheroidal sequences from database. |
dpssdir |
Discrete prolate spheroidal sequences database directory. |
dpssload |
Load discrete prolate spheroidal sequences from database. |
dpsssave |
Save discrete prolate spheroidal sequences in database. |
pmtm |
Power spectrum estimate using the multitaper method (MTM). |
References
[1] Percival, D.B., and A.T. Walden. Spectral Analysis for Physical Applications: Multitaper and Conventional Univariate Techniques. Cambridge: Cambridge University Press, 1993.