regcon.m

PLS_Toolbox是用于故障检测与诊断方面的matlab工具箱

function [a,b] = regcon(mod,xmn,ymn,xst,yst);
%REGCON Converts regression model to y = ax + b form
%  REGCON can be used to convert a model (mod) generated by
%  the function MODLGUI. The outputs are the regression
%  coefficients (a) and the intercept (b) such that 
%  y = ax + b. In this case the I/O syntax is:
%
%I/O: [a,b] = regcon(mod);
%
%  REGCON can also be used to convert the individual parts of a
%  regression model, including the column vector of regression
%  coefficients (regv), predictor variable means (xmn), 
%  predicted variable means (ymn), predictor variable scaling 
%  (xst), and predicted variable scaling (yst).  If xmn or ymn 
%  is not supplied or is set equal to 0 or [], then it is assumed 
%  to be zero (i.e. no centering was used in the model). If xst 
%  or yst is not supplied or is set equal to 0 or [], then it is 
%  assumed to be one (i.e. no scaling was used in the model). 
%
%I/0: [a,b] = regcon(regv,xmn,ymn,xst,yst);
%
%Examples:
%  [a,b] = regcon(mod);                  % using MODLGUI model
%  [a,b] = regcon(regv,xmn,ymn);         % mean centered only
%  [a,b] = regcon(regv,xmn,ymn,xst,yst); % mean centered and scaled
%  [a,b] = regcon(regv,xmn,ymn,[],yst);  % x data centered but not scaled
%  [a,b] = regcon(regv,0,0,xst,yst);     % x and y scaled by not centered
%
%See also: AUTO, MNCN, MODLGUI, MODLPRED, MODLRDER, PCR, PLS, RIDGE, SIMPLS

%Copyright Eigenvector Research, Inc. 1997-98
%bmw 7/97
%bmw 3/98
%bmw 3/99
if strcmp(class(mod),'struct')
  xmn = mod.meanx; ymn = mod.meany; xst = mod.stdx; yst = mod.stdy;
  bb = mod.reg;
  [nxv,nyv] = size(bb);
  if strcmp(mod.scale,'mean') | strcmp(mod.scale,'none')
    xst = ones(size(xst));
	yst = ones(size(yst));
  end
  if strcmp(mod.scale,'none')
    xmn = zeros(size(xmn));
	ymn = zeros(size(ymn));
  end
else
  bb = mod;
  [nxv,nyv] = size(mod);
  if nargin == 1
    xmn = 0; ymn = 0; xst = 0; yst = 0;
  elseif nargin == 2
    ymn = 0; xst = 0; yst = 0;
  elseif nargin == 3
    xst = 0; yst = 0;
  elseif nargin == 4
    yst = 0;
  end
end
if (xmn == 0 | isempty(xmn))
  xmn = zeros(1,nxv);
end
if (xst == 0 | isempty(xst))
  xst = ones(1,nxv);
end
if (ymn == 0 | isempty(ymn))
  ymn == zeros(1,nyv);
end
if (yst == 0 | isempty(yst))
  yst = ones(1,nyv);
end

b = -((xmn./xst)*bb).*yst + ymn;
a = diag(yst)*(bb'./xst(ones(nyv,1),:));