# R Dataset / Package datasets / randu

On this R-data statistics page, you will find information about the randu data set which pertains to Random Numbers from Congruential Generator RANDU. The randu data set is found in the datasets R package. You can load the randu data set in R by issuing the following command at the console data("randu"). This will load the data into a variable called randu. If R says the randu data set is not found, you can try installing the package by issuing this command install.packages("datasets") and then attempt to reload the data with the library() command. If you need to download R, you can go to the R project website. You can download a CSV (comma separated values) version of the randu R data set. The size of this file is about 10,670 bytes.

## Random Numbers from Congruential Generator RANDU

### Description

400 triples of successive random numbers were taken from the VAX FORTRAN function RANDU running under VMS 1.5.

### Usage

randu

### Format

A data frame with 400 observations on 3 variables named `x`

, `y`

and `z`

which give the first, second and third random number in the triple.

### Details

In three dimensional displays it is evident that the triples fall on 15 parallel planes in 3-space. This can be shown theoretically to be true for all triples from the RANDU generator.

These particular 400 triples start 5 apart in the sequence, that is they are ((U[5i+1], U[5i+2], U[5i+3]), i= 0, ..., 399), and they are rounded to 6 decimal places.

Under VMS versions 2.0 and higher, this problem has been fixed.

### Source

David Donoho

### Examples

## We could re-generate the dataset by the following R code seed <- as.double(1) RANDU <- function() { seed <<- ((2^16 + 3) * seed) %% (2^31) seed/(2^31) } for(i in 1:400) { U <- c(RANDU(), RANDU(), RANDU(), RANDU(), RANDU()) print(round(U[1:3], 6)) }

Dataset imported from https://www.r-project.org.