getntrace.m

这是matlab在地球物理数据处理方面的源码

% ****************************************
% *** Program GetnTrace.m Matlab       ***
% *** Reads a trace from a shot gather ***
% *** from files name nshot000.sgy     ***
% *** file must be segy format         ***
% *** Written by Y. Bouzidi            ***
% *** U of Alberta, Physics            ***
% ****************************************
% 
% *** Inputs: ShotNumber and TraceNumber ***
% *** Outputs: trace and its offset ***
% 
      function [trace,offset]=GetnTrace(ShotNumber,TraceNumber);
      nt=1250;
      str='nshot000.sgy';
      s=num2str(ShotNumber);
      if(ShotNumber<10)
        str(8:8)=s;
      else
        str(7:8)=s;
      end
      fid=fopen(str,'r','l');
      fseek(fid,3600+(TraceNumber-1)*(nt+60)*4,'bof');
      trace=fread(fid,nt+60,'float');
      ntrace=trace(61:nt+60);
      trace=ntrace;
      fclose(fid)
      [offset]=GetOffset(str,TraceNumber,TraceNumber);
      return
%
% *** end of program ***