Using the R.cache package

# RStudio instance #1 - the cache saving test piece

# Load R.cache library, set working and cache directories

library("R.cache")

setCacheRootPath(path="C:\\Data Study\\Class 5 Reproducible Research\\Week 4")

setwd("C:\\Data Study\\Class 5 Reproducible Research\\Assignment 2")

# Load a large data file that takes a while to load

data1 <- ata="" bzfile="" div="" read.csv="" tormdata.csv.bz2="">

# Cache the loaded data object using key ABC

# Creates file d125f08eb1bf24d4c1e2b38b35d3362b.Rcache (389,576 KB)

key <- div="" list="">

saveCache(data1,key)

> nrow(data1)

[1] 902297

> ncol(data1)

[1]

                   # RStudio instance #2 (separate UI, process) - the cache reading test piece

                   # Load R.cache library, set working and cache directories

                   library("R.cache")

                   setCacheRootPath(path="C:\\Data Study\\Class 5 Reproducible Research\\Week 4")

                   setwd("C:\\Data Study\\Class 5 Reproducible Research\\Assignment 2")

                   # Load the large cached data object - much faster than original load!

                   key <- b="" list="">

                   dataX <- b="" key="" loadcache="">

                    > nrow(dataX)

                    [1] 902297

                    > ncol(dataX)

                    [1] 37

# Cache the datamod() function  itself

# Creates file f4971f5a1be44fc8fddb87235d45aaaa.Rcache (2 KB)

key <- div="" list="">

saveCache(datamod,key)

                   # Load the datamod() function 

                   key <- b="" list="">

                   dataX <- b="" key="" loadcache="">

                   > dataX(4)

                   [1] 12

# Cache the result of a datamod function call

# Creates file 1b2526c00d8ed8a42700fc0fb39c1b1b.Rcache (1 KB)

key <- div="" list="">

saveCache(datamod(6),key)

                   # Load the datamod() function return value 

                   key <- b="" list="">

                   dataX <- b="" key="" loadcache="">

                   > dataX

                   [1] 18

# Small sample function

datamod <- div="" function="" myarg="">

{

  myarg * 3

}