```{r}
c(1,2) + c(3,5)

c(1,c(2,3))

sqrt(10)
```

```{r}
d <- read.table('http://www.amstat.org/publications/jse/datasets/homes76.dat.txt',
                header=TRUE,sep='\t',stringsAsFactor=TRUE)

summary(d)

colnames(d)

colnames(d) <- c('id', 'Price', 'Size', 'Lot', 'Bath', 'Bed', 'BathBed', 'Year', 'Age',
   'Agesq', 'Garage', 'Status', 'Active', 'Elem', 'Edison Elementary',
   'Harris Elementary', 'Adams Elementary', 'Crest Elementary', 'Parker Elementary')

summary(d)

str(d)

class(d)

typeof(d)

# help(saveRDS)
saveRDS(d,file='tmp.rds')

rm(list=ls())
ls()

d = readRDS(file='tmp.rds')
head(d)

# help(loadRDS)

library(ggplot2)

ggplot(data=d,aes(x=Price,y=Size)) + geom_point() + geom_smooth()
```

