deriver2.m

Savitzky & Golay 微分

function[diff]=deriver2(raw,punkt)
%function[diff]=deriver2(raw,punkt)
%Savitzky & Golay 2.ordens derivasjon langs n-retning, 5,7,9...21 punkts
%antar:raw=n*m=(# retensjonstider)*(# b鴏getall)

[n,m]=size(raw);

convolute5=[2 -1 -2 -1 2];
convolute7=[5 0 -3 -4 -3 0 5];
convolute9=[28 7 -8 -17 -20 -17 -8 7 28];
convolute11=[15 6 -1 -6 -9 -10 -9 -6 -1 6 15];
convolute13=[22 11 2 -5 -10 -13 -14 -13 -10 -5 2 11 22];
convolute15=[91 52 19 -8 -29 -48 -53 -56 -53 -48 -29 -8 19 52 91];
convolute17=[40 25 12 1 -8 -15 -20 -23 -24 -23 -20 -15 -8 1 12 25 40];
convolute19=[51 34 19 6 -5 -14 -21 -26 -29 -30 -29 -26 -21 -14 -5 6 19 34 51];
convolute21=[190 133 82 37 -2 -35 -62 -83 -98 -107 -110 -107 -98 -83 -62 -35 -2 37 82 133 190];

if (punkt == 5)
        convolute = convolute5;
	number=7;        
elseif (punkt == 7)
        convolute = convolute7;
	number=42;
elseif (punkt == 9)
        convolute = convolute9;
	number=462;
elseif (punkt == 11)
        convolute = convolute11;
	number=429;
elseif (punkt == 13)
        convolute = convolute13;
	number=1001;
elseif (punkt == 15)
        convolute = convolute15;
	number=6188;
elseif (punkt == 17)
        convolute = convolute17;
	number=3876;
elseif (punkt == 19)
        convolute = convolute19;
	number=6783;
else
        convolute = convolute21;
	number=33649;
end;

start=(punkt+1)/2;
slutt=(n+(punkt-1)/2);
for i=1:m
        a(:,1)=raw(:,i);
        b=conv(convolute,a);
        diff(:,i)=b(start:slutt)./number;
end;