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/shft.m
function [dataout]=shft(datain,scale,word) %[dataout]=shft(datain,scale,word) % %This function requires input data in DSI format. %A time shift will be applied or removed on a per trace basis %by an amount given in trace header word 'word'. %Shifts are to the nearest sampling point. % %scale is what the desired time shifts will be multiplied by %1.0: Apply static shift %-1.0: Remove previously applied shifts % %word is the trace header word containing the time in seconds %by which the trace is to be shifted % %Shifts will be applied to all traces and records. % %Convention: positive value = shift traces down % negative value = shift traces up % % Warning: Program does not check for reasonable parameters % %DSI customized VSP processing software %Written by Marko Mah January 1999 %$Id: shft.m,v 3.0 2000/06/13 19:22:03 gilles Exp $ %$Log: shft.m,v $ %Revision 3.0 2000/06/13 19:22:03 gilles %Release 3 % %Revision 2.0 1999/05/21 18:46:35 mah %Release 2 % %Revision 1.4 1999/05/21 15:11:38 mah %eof problem % %Revision 1.3 1999/05/21 15:10:41 mah %eof problem % %Revision 1.2 1999/02/09 21:58:02 mah %fixed up shift because it was off by one sample % %Revision 1.1 1999/01/26 19:45:45 mah %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]=shft(datain,scale,word)'); dataout=datain; nrec=datain.fh{12}; %number of records int=datain.fh{8}; %sampling interval (sec) samples=datain.fh{7}; %number of points per trace for COUNT1=1:nrec [a,ntraces]=size(datain.dat{COUNT1}); %ntraces is the number of traces in the record dataout.dat{COUNT1}(:,1:ntraces)=0; %initialize traces for COUNT2=1:ntraces %takes shift times from trace header word 'word' shift=datain.th{COUNT1}(word,COUNT2); shift=shift*scale; %multiplies shift by scale to get "total" shift index=round(abs(shift)/int); %converts shift from time to samples if index==0 %no shift dataout.dat{COUNT1}(:,COUNT2)=datain.dat{COUNT1}(:,COUNT2); elseif shift<0 %shift upwards dataout.dat{COUNT1}(1:(samples-index),COUNT2)=datain.dat{COUNT1}(index+1:samples,COUNT2); else %shift downwards dataout.dat{COUNT1}(index+1:samples,COUNT2)=datain.dat{COUNT1}(1:(samples-index),COUNT2); end %if index end %for COUNT2 end %for COUNT1