KL变换的Matlab实现

function wigb(a,scal,x,z,amx) %WIGB: Plot seismic data using wiggles. % % WIGB(a,scal,x,z,amx) % % IN a: seismic data (a matrix, traces are columns) % scale: multiple data by scal % x: horizontal axis (often offset) % z: vertical axis (often time) % % Note % % If only 'a' is enter, 'scal,x,z,amn,amx' are set automatically; % otherwise, 'scal' is a scalar; 'x, z' are vectors for annotation in % offset and time, amx are the amplitude range. % % % Author(s): Xingong Li (Intseis, Integrated Seismic Solutions) % Copyright 1998-2003 Xingong % Revision: 1.2 Date: Dec/2002 % if nargin == 0, nx=10;nz=10; a = rand(nz,nx)-0.5; end; [nz,nx]=size(a); trmx= max(abs(a)); if (nargin <= 4); amx=mean(trmx); end; if (nargin <= 2); x=[1:nx]; z=[1:nz]; end; if (nargin <= 1); scal =1; end; if nx <= 1; disp(' ERR:PlotWig: nx has to be more than 1');return;end; % take the average as dx dx1 = abs(x(2:nx)-x(1:nx-1)); dx = median(dx1); dz=z(2)-z(1); xmx=max(max(a)); xmn=min(min(a)); if scal == 0; scal=1; end; a = a * dx /amx; a = a * scal; fprintf(' PlotWig: data range [%f, %f], plotted max %f \n',xmn,xmx,amx); % set display range x1=min(x)-2.0*dx; x2=max(x)+2.0*dx; z1=min(z)-dz; z2=max(z)+dz; set(gca,'NextPlot','add','Box','on', ... 'XLim', [x1 x2], ... 'YDir','reverse', ... 'YLim',[z1 z2]); fillcolor = [0 0 0]; linecolor = [0 0 0]; linewidth = 1.; z=z'; % input as row vector zstart=z(1); zend =z(nz); for i=1:nx, if trmx(i) ~= 0; % skip the zero traces tr=a(:,i); % --- one scale for all section s = sign(tr) ; i1= find( s(1:nz-1) ~= s(2:nz) ); % zero crossing points npos = length(i1); %12/7/97 zadd = i1 + tr(i1) ./ (tr(i1) - tr(i1+1)); %locations with 0 amplitudes aadd = zeros(size(zadd)); [zpos,vpos] = find(tr >0); [zz,iz] = sort([zpos; zadd]); % indices of zero point plus positives aa = [tr(zpos); aadd]; aa = aa(iz); % be careful at the ends if tr(1)>0, a0=0; z0=1.00; else, a0=0; z0=zadd(1); end; if tr(nz)>0, a1=0; z1=nz; else, a1=0; z1=max(zadd); end; zz = [z0; zz; z1; z0]; aa = [a0; aa; a1; a0]; zzz = zstart + zz*dz -dz; patch( aa+x(i) , zzz, fillcolor); line( 'Color',[1 1 1],'EraseMode','background', ... 'Xdata', x(i)+[0 0], 'Ydata',[zstart zend]); % remove zero line %'LineWidth',linewidth, ... %12/7/97 'Xdata', x(i)+[0 0], 'Ydata',[z0 z1]*dz); % remove zero line line( 'Color',linecolor,'EraseMode','background', ... 'LineWidth',linewidth, ... 'Xdata', tr+x(i), 'Ydata',z); % negatives line else % zeros trace line( 'Color',linecolor,'EraseMode','background', ... 'LineWidth',linewidth, ... 'Xdata', [x(i) x(i)], 'Ydata',[zstart zend]); end; end;