In jr-packages/jrBig: Jumping Rivers: R for Big Data

Exercise 1

1. Load the ff package r library("ff")
2. Create a dummy csv file and compare the read times of read.csv.ffdf and read.csv

ffx = read.csv.ffdf(file = filename, header = TRUE)
dd = read.csv(file = filename, header = TRUE)

Solutions

dd = matrix(rnorm(1e5), ncol = 100)
write.csv(dd, "/tmp/tmp.csv")
library("ff")
system.time(read.csv.ffdf(file = "/tmp/tmp.csv", header = TRUE))
system.time(read.csv(file = "/tmp/tmp.csv", header = TRUE))

jr-packages/jrBig documentation built on Jan. 1, 2020, 2:02 p.m.