Можно переопределить всю функцию при каждом запуске R, возможно, расширить функцию дополнительным аргументом digits
:
plot.regsubsets<-function(x,labels=obj$xnames,main=NULL,
scale=c("bic","Cp","adjr2","r2"),
col=gray(seq(0,0.9,length=10)),digits=2,...){
obj<-x
lsum<-summary(obj)
par(mar=c(7,5,6,3)+0.1)
nmodels<-length(lsum$rsq)
np<-obj$np
propscale<-FALSE
sscale<-pmatch(scale[1],c("bic","Cp","adjr2","r2"),nomatch=0)
if (sscale==0)
stop(paste("Unrecognised scale=",scale))
if (propscale)
stop(paste("Proportional scaling only for probabilities"))
yscale<-switch(sscale,lsum$bic,lsum$cp,lsum$adjr2,lsum$rsq)
up<-switch(sscale,-1,-1,1,1)
index<-order(yscale*up)
colorscale<- switch(sscale,
yscale,yscale,
-log(pmax(yscale,0.0001)),-log(pmax(yscale,0.0001)))
image(z=t(ifelse(lsum$which[index,],
colorscale[index],NA+max(colorscale)*1.5)),
xaxt="n",yaxt="n",x=(1:np),y=1:nmodels,xlab="",ylab=scale[1],col=col)
laspar<-par("las")
on.exit(par(las=laspar))
par(las=2)
axis(1,at=1:np,labels=labels)
axis(2,at=1:nmodels,labels=signif(yscale[index],digits))
if (!is.null(main))
title(main=main)
box()
invisible(NULL)
}