freqgrad<-function(datami=gardonmi,nomvar="G",nomy="gardon", ncla=10) {



	x0<-datami[,nomvar]



	yobs<-datami[,nomy]



	if (is.numeric(x0)==F) return ("Numeric data need")



	q0<-quantile(x0,probs = seq(0,1,1/ncla), na.rm = F)



	c.cla<-quantile(x0,probs=seq(0+1/2/ncla,1-1/2/ncla,1/ncla),na.rm=F)



	xmin<-min(x0)



	xmax<-max(x0)



	q1<-cut(x0,q0, include.lowest = T)



	t0<-table(q1,yobs)



	t0[, 1] <- (t0[, 1] + t0[, 2])



	freq<-t0[,2]/t0[,1]



	toto1<-rep(0,ncla)



	toto2<-rep(0,ncla)



	for(i in 1:ncla) {



		succes <- t0[i, 2]



		essai <- t0[i, 1]



		if(essai > 10) {



			a0 <- prop.test(succes, essai)$conf.int



			toto1[i] <- a0[1]



			toto2[i] <- a0[2]



			if(a0[1] > freq[i]) toto1[i] <- NA



			if(a0[2] < freq[i]) toto2[i] <- NA



		} else {



			toto1[i] <- NA



			toto2[i] <- NA



		}



	}



	ymin<- min(toto1,na.rm=T)



	ymax<- max(toto2,na.rm=T)



	plot(xmin,0,ylim=c(ymin,ymax),xlim=c(xmin,xmax),



	ylab="proba",xlab=nomvar,type="n")



	points(c.cla,freq,pch=16)



	for (i in 1:ncla) {



		if (!is.na(toto1[i])) {



			error.bar(c.cla[i],freq[i],toto1[i],toto2[i],



			add=T,incr=F,gap=F)



		}



		if (i>1) {



			abline(v=q0[i],lty=2)



		}



	}



}