calcmomentgenfun.sci

来自「小波分解源代码」· SCI 代码 · 共 46 行

function tau = CalcMomentGenFun(z,scale,loscale,hiscale)
// CalcMomentGenFun -- Calculate Moment Generating Function
//  Usage
//    tau = CalcMomentGenFun(z,a,loscale,hiscale)
//  Inputs
//    z         matrix nexp by nscale of z(q,a) ``Thermo Partition Func''
//    a         list of scales 
//    loscale   optional min scale to fit line by
//    hiscale   optional max scale to fit line by 
//  Outputs
//    tau       vector 1 by nscale of moments
//
//  Description
//    tau(q) = Slope [ log(z(q,a))  versus log(a) ]
//
//  See Also
//    CalcThermoPartition
//
//  Copyright Aldo I Maalouf

[lhs,rhs]=argn();
	if rhs < 3,
		loscale = 0.;
		hiscale = 10^32;
	end
	
	
	[nq,nscale]     = size(z);
	tau = zeros(nq,1);
	if nscale ~= size(scale),
		disp('CalcMomentGenFun: no match between z and a')  
	end
	
	window = (loscale <= scale) & (scale <= hiscale);
	ix     = find(window);
	if length2(ix)>1,
		for kq =1:nq,
		 	y       =  log(z(kq,ix));   y = y-mean(y);
			x       =  log(scale(ix));  x = x-mean(x);				
			tau(kq) = sum(y.*x) / sum(x.*x);
		end
	else
		disp('CalcMomentGenFun: not enough data to determine slope')
	end 	 
 endfunction