impulse.m

著名的seismiclab的代码 是地震学研究人员必备的工具

function [D] = impulse(nt,nx,f,dt);
%IMPULSE: 2D bamdlimited impulse
%
%  Place a wavelet of central frequency f in the 
%  center of an x-t grid.
%
%  [D] = impulse(nt,nx,f,dt);
%
%  IN    nt: number of time samples (vertical samples)
%        nx: number of horizontal samples
%        f:  central freq. of the Ricker wavelet in Hz
%        dt: sampling interval  in sec
%
%  OUT   D:  a matrix with a ricker wavelet in the center
%
%  Example:
%          wigb(impulse(100,20,25,0.004));
%
%         
%  SeismicLab
%  Version 1
%
%  written by M.D.Sacchi, last modified December 10,  1998.
%  [e-mail]
%
%  Copyright (C) 1998 Seismic Processing and Imaging Group
%                     Department of Physics
%                     The University of Alberta
%
%


wave = ricker(f,dt);  nw = max(size(wave));

D = zeros(nt,nx); 
n=floor(nt/2)-floor(nw/2);
D(n:n+nw-1,nx/2) = wave(:); 

return