fund.m

这是在网上下的一个东东

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% Computes forward model predictions for the EM-38 problem.
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function f=fund(sigma)
global DATA;
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% Number of layers.
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M=11;
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% Layer thicknesses.
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D=0.2*ones(10,1);
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% Operating frequency.
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f=14600;
OMEGA=2*pi*f;
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% Distance between coils.
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R=1.0;
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% Conductivity of the air above the top layer.
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SIGMA0=0;
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% Magnetic permeabilities.
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MU0=pi*4e-7;
MU=MU0*ones(11,1);
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% Scaling factor Delta.
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DELTA=sqrt(2/(sigma(1)*MU0*OMEGA));
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% Heights of measurements.
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heights=[0.0; 0.1; 0.2; 0.3; 0.4; 0.5; 0.75; 1.0; 1.50];
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% Now, do the predictions.
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pred=[];
pred=zeros(length(heights),2);
for i=1:length(heights)
  H=heights(i);
  [predv,predh]=predict(R,DELTA,H,M,MU,MU0,sigma,SIGMA0,D,OMEGA);
  pred(i,:)=[predv predh];
end
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% Stack up the predictions (vertical over horizontal)
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f=[pred(:,1); pred(:,2)]-DATA;