www.pudn.com > logtools.rar > gardner.m, change:2004-08-13,size:2946b

function rho=gardner(v,a,m,rho)  % rho=gardner(v,a,m,rho) % rho=gardner(v,a,m) % % GARDNER estimates a density vector given an instantaneous velocity vector % and values for the empirical parameters a and m via the Gardner relation %	rho=a*v.^m (a times v to the mth power) % If a partial density vector is available, then it may be provided as a 4th % argument which must be expanded with NaN's to be the same length as v. (Take  % care that the existing densities are paired with the proper v's.) Densities % will only be computed with Garnders relation where they are missing and any % non-NaN input densities are simply passed to output. % 	v= vector of instantaneous p-wave velocities %	a= scalar multplier %		*********** default is .31 ********** %	m= scalar exponent %		*********** default is .25 ********** %	rho= on input, a vector of known densities which must be expanded with  %		NaN's to be the same size as v %	rho= on output, aa vector of densities the same size as v and computed %		via Gardner's relation where densities were missing on input. % % G.F. Margrave, March 1994 % % 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:  crewesinfo@crewes.org %  % 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   if(nargin<4) 	rho=nan*ones(size(v)); end  if(nargin<3) 	m=.25; end  if(nargin<2) 	a=.31; end  ind=find(isnan(rho));  rho(ind)= a*v(ind).^m;