data
dt <- data.frame(ID=1:20, conc=rnorm(100, 25), gene1=sample(0:2, 20, replace=TRUE),
gene2=sample(0:2, 20, replace = TRUE), gene3 = sample(0:2, 20, replace=TRUE))
geneNames = names(dt)[3:5]
for(i in geneNames)
{
boxplot(conc~as.factor(i), data=dt)
}
为什么不能循环呢? 该怎样修改呢? 请指教!