extract values from xls files

extract.r

# JDK required, install jdk on mac with:
# R CMD javareconf JAVA_CPPFLAGS=-I/System/Library/Frameworks/JavaVM.framework/Headers
require(xlsx) 
#file <- system.file("/tmp/", "cobbdoug.xlsx", package = "xlsx")
wb <- loadWorkbook("/tmp/cobbdoug.xlsx") 
sheets <- getSheets(wb) # get all sheets
sheet <- sheets[['cobbdoug.xls']] # get sheet with name "cobbdoug.xls"
rows  <- getRows(sheet)

cells <- getCells(rows, colIndex=2)

# apply getCellValue() function to all cells, return a list
values <- lapply(cells, getCellValue) 
len = length(values) 

# extract list values to a vector, without names
Q <- unlist(values, use.names = FALSE)

# convert characters in subvector to number, 
Q <- as.numeric(Q[2:len])

cells <- getCells(rows, colIndex=3)
values <- lapply(cells, getCellValue) 
K <- unlist(values, use.names = FALSE)
K <- as.numeric(K[2:len])

cells <- getCells(rows, colIndex=4)
values <- lapply(cells, getCellValue) 
L <- unlist(values, use.names = FALSE)
L <- as.numeric(L[2:len])