Hi,
I try to minimize the sum of the sum of sce. The following program has
been
created but it only takes in consideration the last kinetic and not the
first ones. I think that I have forget a subscrib but I don't know
where. so
if you can help me, it will be great....
I have try an other program where y and x are directly calculate in sce
function but the time of running was to long.
Thanks in advance,
Anne KERVAHU
rm(list=ls())
nbr=10
#list of data
x_a<-c(0,0.5,1,1.5,2,3,4,6,8,15,20,40,60,80,120)
y_a<-c(5.4771213,5.0791812,4.8450980,4.3010300,4,2.30103,1.5563025,1.30103,1
,1.6434527,0.60206,0.60206,0.30103,0,0.4771213)
x_b<-c(0,1,2,3,4,5,6,7,8,9,10,11,12,13,14)
y_b<-c(5.3424227,4.9867717,4.6627578,4.0606978,3.07182,3.4771213,2.7993405,2
.9395193,2.69897,2.6127839,1.9777236,1.3222193,1.4149733,0.7781513,1.322219)
x_c<-c(0,3,6,10,12,14,16,18,20,24,26,28,30,34)
y_c<-c(5.5185139,5.1461280,4.3617278,3.771513,3.20412,3.0413927,2.7781513,2.
5682017,2.255272,1.7823917,1.447158,1.3222193,1.2787536,0.69897)
#number of kinetics
nb=3
#complete data set
x<-c(x_a,x_b,x_c)
y<-c(y_a,y_b,y_c)
#cumulative length
long<-c(0,15,30,44)
coeff<-matrix(nrow=1,ncol=(nb*2)+2)
#function to minimise
sce<-function(param){
return(sum(sum((yy-(param[i+nb]-(xx/param[i])^param[(nb*2)+1]))^2)))
}
#initial value for optim function
ninit<-vector(length=nb)
for(i in 1:nb){
ninit[i]<-x[long[i]+1]
}
pinf=c(rep(0.01,nb),rep(3,nb),0.5)
psup=c(rep(10,nb),rep(8,nb),4)
pinit=c(runif(nb,min=0.1,max=5),ninit,runif(1,min=0.5,max=4))
print(pinit)
for (i in 1:nb)
{
yy<-y[((long[i]+1):long[i+1])]
for( k in 1:length(yy)){
ifelse((yy[k]<=log10(nbr)),(yy<-yy[1:(min(which(yy<=log10(nbr),arr.ind=FALSE
))-1)]),(yy<-yy))
}
vv<-x[((long[i]+1):long[i+1])]
xx<-x[((long[i]+1):((long[i]+1)+(length(vv)=length(yy))-1))]
fl<-optim(p=pinit,sce,method="L-BFGS-B",lower=pinf,upper=psup,
control=list(maxit=200000,temp=200))
co<-fl$par
coe<-fl$value
coeff<-c(co,coe)
}
coeff
#graphical verification
plot(x_b,y_b)
y_est<-coeff[6]-(x_b/coeff[2])^coeff[7]
points(x_b,y_est)
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