gusucode.com > DSISoft是由加拿大地质调查局发布的用于垂直地震剖面(VSP)数据处理的免费软件包 > dsisoftv3/dsisoftv3/dsisoftv3/main/tred.m
function [dataout]=tred(datain,v,shift) %[dataout]=tred(datain,v,shift) % %This function requires input data in DSI format. It takes the velocity %of the waves, v (m/s), and flattens the data using this information and %the source-receiver offset distance found in trace header word 53. A time %shift can be applied also by an amount given in the parameter 'shift' (sec). %Shifts are to the nearest sampling point so trim statics should be %applied to achieve better alignment if needed. All time shifts will be %recorded in trace header word 8 in seconds. % %Convention: positive value = shift traces down % negative value = shift traces up % %DSI customized VSP processing software %written by Kristen Beaty November, 1997 %$Id: tred.m,v 3.0 2000/06/13 19:22:23 gilles Exp $ %$Log: tred.m,v $ %Revision 3.0 2000/06/13 19:22:23 gilles %Release 3 % %Revision 2.0 1999/05/21 18:46:53 mah %Release 2 % %Revision 1.1 1999/01/06 19:09:10 kay %Initial revision % % %Copyright (C) 1998 Seismology and Electromagnetic Section/ %Continental Geosciences Division/Geological Survey of Canada % %This library is free software; you can redistribute it and/or %modify it under the terms of the GNU Library General Public %License as published by the Free Software Foundation; either %version 2 of the License, or (at your option) any later version. % %This library is distributed in the hope that it will be useful, %but WITHOUT ANY WARRANTY; without even the implied warranty of %MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU %Library General Public License for more details. % %You should have received a copy of the GNU Library General Public %License along with this library; if not, write to the %Free Software Foundation, Inc., 59 Temple Place - Suite 330, %Boston, MA 02111-1307, USA. % %DSI Consortium %Continental Geosciences Division %Geological Survey of Canada %615 Booth St. %Ottawa, Ontario %K1A 0E9 % %email: dsi@cg.nrcan.gc.ca disp('[dataout]=tred(datain,v,shift)'); dataout=datain; nrec=datain.fh{12}; int=datain.fh{8}; %sampling interval (sec) tstart=datain.fh{9}; %start time (sec) samples=datain.fh{7}; %number of points per trace for COUNT=1:nrec %loop over records dataout.dat{COUNT}(:,:)=0; %initialize dataout.dat times(1,:)=datain.th{COUNT}(53,:)./v+shift; %put shift times into trace headers dataout.th{COUNT}(8,:)=dataout.th{COUNT}(8,:)+times(1,:); indexes=round((abs(times(1,:))-tstart)./int); for i=1:length(indexes) %loop over number of traces index=indexes(i); if index==0 %no shift dataout.dat{COUNT}(:,i)=datain.dat{COUNT}(:,i); elseif times(i)<0 %shift upwards dataout.dat{COUNT}(1:(samples-index+1),i)=datain.dat{COUNT}(index:samples,i); else %shift downwards dataout.dat{COUNT}(index:samples,i)=datain.dat{COUNT}(1:(samples-index+1),i); end %if end %loop over number of traces end %loop over records