Parsing multiple Matrices from multiple Files at once

Question

I have a folder Bad with "bad" samples in form of several csv-Files with numerical values. The idea is to parse to them and use the matrices with the correct column names. The matrices should then be in the list bad_list.

  setwd("Bad")
  bad <- list.files(pattern="*.csv")
  bad_list = lapply(bad, read.csv, sep = ";", stringsAsFactors=FALSE, header=TRUE)

The result of

bad_list[1]

is a nice matrix. However, the result for the following

colnames(bad_list[1])
ncol(bad_list[1])

is NULL for both commands. Any ideas?

A case of `[` vs `[[`? Check `str(bad_list[1])` and `str(bad_list[[1]])`. — Henrik, Sep 03 '14 at 08:41
See http://stackoverflow.com/questions/1169456/in-r-what-is-the-difference-between-the-and-notations-for-accessing-the/ — Henrik, Sep 03 '14 at 08:46

score 0 · Accepted Answer · answered Sep 04 '14 at 05:19

0

Using bad_list[[1]] does it. [[ ]] is the index-operator for lists.

answered Sep 04 '14 at 05:19

Joachim

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Parsing multiple Matrices from multiple Files at once

1 Answers1