R long table wide table convertion

R long table wide table convertion.R

#### long data to wide data
long.data <- read.csv(textConnection("ID,Month,Sale
1,1,100
1,2,123
1,3,456
1,4,45
1,5,486
2,1,200
2,2,131
2,3,423
2,4,486
2,5,1
3,1,300
3,2,123
3,3,456
3,4,864
3,5,486
4,1,300
4,2,123
4,3,45
4,4,48
4,5,90
5,1,300
5,2,5563
5,3,1
5,4,53
5,5,15"))

# optional
long.data$Month <- factor(long.data$Month, labels=c("M1", "M2", "M3", "M4", "M5"))

## using reshape2::dcast()
library(reshape2)
dcast(long.data, ID ~ Month, value.var = "Sale")

## using tidyr::spread()
library(tidyr)
spread(long.data, Month, Sale

#### wide data to long data
wide.data <- read.csv(textConnection("ID,Month1,Month2,Month3,Month4,Month5
1,100,123,456,45,486
2,200,131,423,486,1
3,300,123,456,864,486
4,300,123,45,48,90
5,300,5563,1,53,15"))

## using reshape2::melt()
melt(wide.data, id.vars = c("ID"))

## using tidyr::gather()
gather(wide.data, Month, Sale, Month1:Month5)