RODBC vs gdata
On Mon, Jan 9, 2012 at 1:02 PM, Christof Klu? <ckluss at email.uni-kiel.de> wrote:
Hi
one col in my Excel file contains many numbers. But on line 3000 and
some other lines are strings like "FG 1". "RODBS" seems to omit this
lines. "gdata" works, but is much slower.
Is this a bug of RODBC or do I apply it wrong?
Example with the same "file.xlsx"
library(RODBC); excel <- odbcConnectExcel2007("file.xlsx")
tab <- sqlQuery(excel, 'select * from "Table 1$"'); str(tab)
col1: num ?1 2 3 4 5 6 7 8 9 10 ...
library(gdata); tab <- read.xls("file.xlsx", sheet=1); str(tab)
col1: Factor w/ 51 levels "1","10","11",..: 1 12 23 34 41 42 43...
You might be able to speed up read.xls in gdata. Try turning off comment characters and setting colClasses, e.g. DF <- read.xls(...whatever..., comment.char = "", colClasses = ...whatever...)
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