Attaching a big.matrix object
Now that the big.matrix object is on the disk, we can use the information stored in the descriptor file to instantly make it available during an R session. This means that you don't have to reimport the data set, which takes more time for larger files. You can simply point the bigmemory package at the existing structures on the disk and begin accessing data without the wait.
Cet exercice fait partie du cours
Scalable Data Processing in R
Instructions
The big.matrix object x is available in your workspace.
- Create a new variable
mortthat points toxby attaching the"mortgage-sample.desc"file using theattach.big.matrix()function. - Verify that the dimensions of
mortare the same as the last exercise. - Call
head()onmort.
Exercice interactif pratique
Essayez cet exercice en complétant cet exemple de code.
# Attach mortgage-sample.desc
mort <- ___(___)
# Find the dimensions of mort
___
# Look at the first 6 rows of mort
___