Hi Everyone,
?
I am trying to import many CSV files to their own matrices. Example, alaska_93.csv to alaska. When I execute the following, for each csv.file separately it is successful.
?
singleCSVFile2Matrix <- function(x,path) {
?assign(gsub(pattern=".csv",x,replacement=""),read.csv(paste(path,x,sep="")))
}
?
when I try to include it in a loop in another function (I have so many csv files to import), it doesn't work. I mean the following function doesn't do it.
?
loadCSVFiles_old <- function(path) {
?x <- list.files(path)
?for (i in 1:length(x)) {
??assign(gsub(pattern=".csv",x[i],replacement=""),read.csv(paste(path,x[i],sep="")))
??}
}
?
Instead, if I execute the foor loop in the command line, it works. I am puzzled. Appreciate any help.
?
thanks
yetik
importing many csv files into separate matrices
2 messages · yetik serbest, David Winsemius
On Nov 27, 2013, at 2:39 PM, yetik serbest wrote:
Hi Everyone,
I am trying to import many CSV files to their own matrices. Example, alaska_93.csv to alaska. When I execute the following, for each csv.file separately it is successful.
singleCSVFile2Matrix <- function(x,path) {
assign(gsub(pattern=".csv",x,replacement=""),read.csv(paste(path,x,sep="")))
}
when I try to include it in a loop in another function (I have so many csv files to import), it doesn't work. I mean the following function doesn't do it.
loadCSVFiles_old <- function(path) {
x <- list.files(path)
for (i in 1:length(x)) {
assign(gsub(pattern=".csv",x[i],replacement=""),read.csv(paste(path,x[i],sep="")))
}
}
It appears you are not returning the values that you created inside that function to the global environment. I would have expected that you would either given `assign` an environment argument or that you would have created a list of items to return from the function.
?environment
?assign
Perhaps:
loadCSVFiles_old <- function(path) {
x <- list.files(path)
for (i in 1:length(x)) {
assign(gsub(pattern=".csv",x[i],replacement=""),
read.csv(paste(path,x[i],sep="")))
envir=.GlobalEnv
}
}
Instead, if I execute the foor loop in the command line, it works. I am puzzled. Appreciate any help. thanks yetik
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David Winsemius Alameda, CA, USA