twoptcircle.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 [xc,yc,radius] = twoptcircle(xp,yp,n)

% [xc,yc,radius] = twoptcircle(xp,yp,n)
% [xc,yc,radius] = twoptcircle(xp,yp)
%
% TWOPTCIRCLE takes two points, and makes a circle with point 1 as the
% center, and point 2 defining the radius.
%
% xp	= x-coordinates for point1 and point2, i.e. x(1) and x(2)
% yp	= y-coordinates for point1 and point2, i.e. y(1) and y(2)
% n	= number of points on the circle
% **************************** Default = 30 *******************************
%
% xc	= x-coordinates for points on circle
% yc	= y-coordinates for points on circle
%
%  T. N. BISHOP,  OCTOBER 1993,  CPTC CANADA
%
% 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.
%
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%    use this SOFTWARE subject to the following terms and conditions:
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% END TERMS OF USE LICENSE

if nargin<3
	n=30;
end

radius = sqrt( (xp(2)-xp(1)).^2 + (yp(2)-yp(1)).^2 );
for i = 1:n
  t(i) = (i-1)*2.*pi/n;
end
t = [t,t(1)];
  xc=xp(1) + radius*cos(t);
  yc=yp(1) + radius*sin(t);