sgwt_framebounds : Compute approximate frame bounds for given sgw transform function [A,B,sg2,x]=sgwt_framebounds(g,lmin,lmax) Inputs : g - function handles computing sgwt scaling function and wavelet kernels lmin,lmax - minimum nonzero, maximum eigenvalue Outputs : A , B - frame bounds sg2 - array containing sum of g(s_i*x)^2 (for visualization) x - x values corresponding to sg2
0001 % sgwt_framebounds : Compute approximate frame bounds for given sgw transform 0002 % 0003 % function [A,B,sg2,x]=sgwt_framebounds(g,lmin,lmax) 0004 % 0005 % Inputs : 0006 % g - function handles computing sgwt scaling function and wavelet 0007 % kernels 0008 % lmin,lmax - minimum nonzero, maximum eigenvalue 0009 % 0010 % Outputs : 0011 % A , B - frame bounds 0012 % sg2 - array containing sum of g(s_i*x)^2 (for visualization) 0013 % x - x values corresponding to sg2 0014 0015 % This file is part of the SGWT toolbox (Spectral Graph Wavelet Transform toolbox) 0016 % Copyright (C) 2010, David K. Hammond. 0017 % 0018 % The SGWT toolbox is free software: you can redistribute it and/or modify 0019 % it under the terms of the GNU General Public License as published by 0020 % the Free Software Foundation, either version 3 of the License, or 0021 % (at your option) any later version. 0022 % 0023 % The SGWT toolbox is distributed in the hope that it will be useful, 0024 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0025 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0026 % GNU General Public License for more details. 0027 % 0028 % You should have received a copy of the GNU General Public License 0029 % along with the SGWT toolbox. If not, see <http://www.gnu.org/licenses/>. 0030 0031 function [A,B,sg2,x]=sgwt_framebounds(g,lmin,lmax) 0032 N=1e4; % number of points for line search 0033 x=linspace(lmin,lmax,N); 0034 Nscales=numel(g); 0035 0036 sg2=zeros(size(x)); 0037 for ks=1:Nscales 0038 sg2=sg2+(g{ks}(x)).^2; 0039 end 0040 A=min(sg2); 0041 B=max(sg2); 0042 0043