desigpoly.m

基于matlab的反演程序,用于地球物理勘探中射线追踪及偏移成像程序.

function [q,r]=desigpoly(b,a)

% q= desigpoly(b,a)
% [q,r]= desigpoly(b,a)
%
% This is a modification of MATLAB's DECONV function to behave as
% a typical seismic designature algorithm. 'b' contains a seismic
% trace while 'a' contains a signature to be removed from 'b' 
% using MATLAB's DECONV algorithm. The length of the resultant, 'q',
% is equal to the length of 'b'.
% 
%DECONV  Deconvolution.
%	[Q,R] = DECONV(B,A) deconvolves vector A out of vector B.  The result
%	is returned in vector Q and the remainder in vector R such that
%	B = conv(Q,A) + R.   See also CONV.
%
%	If A and B are vectors of polynomial coefficients, deconvolution
%	is equivalent to polynomial division.  The result of dividing B by
%	A is quotient Q and remainder R.
%
%	J.N. Little 2-6-86
%	Copyright (c) 1985, 1986 by the MathWorks, Inc.
%
% modified to DESIG by G.F. Margrave, May 1991
% NOTE: It is illegal for you to use this software for a purpose other
% than non-profit education or research UNLESS you are employed by a CREWES
% Project sponsor. By using this software, you are agreeing to the terms
% detailed in this software's Matlab source file.
 
% BEGIN TERMS OF USE LICENSE
%
% This SOFTWARE is maintained by the CREWES Project at the Department
% of Geology and Geophysics of the University of Calgary, Calgary,
% Alberta, Canada.  The copyright and ownership is jointly held by 
% its author (identified above) and the CREWES Project.  The CREWES 
% project may be contacted via email at:  [e-mail]
% 
% The term 'SOFTWARE' refers to the Matlab source code, translations to
% any other computer language, or object code
%
% Terms of use of this SOFTWARE
%
% 1) Use of this SOFTWARE by any for-profit commercial organization is
%    expressly forbidden unless said organization is a CREWES Project
%    Sponsor.
%
% 2) A CREWES Project sponsor may use this SOFTWARE under the terms of the 
%    CREWES Project Sponsorship agreement.
%
% 3) A student or employee of a non-profit educational institution may 
%    use this SOFTWARE subject to the following terms and conditions:
%    - this SOFTWARE is for teaching or research purposes only.
%    - this SOFTWARE may be distributed to other students or researchers 
%      provided that these license terms are included.
%    - reselling the SOFTWARE, or including it or any portion of it, in any
%      software that will be resold is expressly forbidden.
%    - transfering the SOFTWARE in any form to a commercial firm or any 
%      other for-profit organization is expressly forbidden.
%
% END TERMS OF USE LICENSE


[mb,nb] = size(b);
nb = max(mb,nb);
na = length(a);
q = 0;
if na > nb
	q = 0;
	r = b;
	return
end
if a(1)==0
	error('First coefficient of A must be non-zero.')
end
% Deconvolution and polynomial division are the same operations
% as a digital filter's impulse response B(z)/A(z):
%keyboard
q = filter(b, a, [1 zeros(1,nb-1)]);
%keyboard
if mb ~= 1
	q = q(:);
end
r = b - convm(q,a);