Hello all, I have a CSV file, that is 2411 columns wide. There are certain instances in teh file, where null values are located. That is: two commas together, without anything in the middle. In a certain section, the only possible values are NULL, 0,1,and 2. I need to be able to detect these NULL's and be able to have them counted. For example, in a frequency table. How can I accomplish this? Thanks in advance for the help. -- Jason Thibodeau [[alternative HTML version deleted]]
What have you tried this far? Can't you parse them as missing values, i.e. NAs? See ?read.csv and arguments '...', i.e. the arguments '...' are passed to read.table() which takes argument 'na.strings' - a character *vector* of strings that you want to be interpreted as NAs. See ?read.table for more details. My $.02 Henrik On Thu, Sep 18, 2008 at 10:11 AM, Jason Thibodeau <jbloudg20 at gmail.com> wrote:> Hello all, > > I have a CSV file, that is 2411 columns wide. There are certain instances in > teh file, where null values are located. That is: two commas together, > without anything in the middle. In a certain section, the only possible > values are NULL, 0,1,and 2. I need to be able to detect these NULL's and be > able to have them counted. For example, in a frequency table. How can I > accomplish this? > > Thanks in advance for the help. > > -- > Jason Thibodeau > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >
Try length(na.omit(<the particular data column>))
Here's an example:
data <- runif(100,0,10)
data[runif(20,0,100)] <- NA
file.contents <- matrix(data, ncol = 5, byrow = TRUE)
for (i in 1:5) {
print (length(na.omit(file.contents[,i])))
}
-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
On Behalf Of Jason Thibodeau
Sent: Thursday, September 18, 2008 10:12 AM
To: r-help at r-project.org
Subject: [R] detecting null values in a CSV file
Hello all,
I have a CSV file, that is 2411 columns wide. There are certain
instances in
teh file, where null values are located. That is: two commas together,
without anything in the middle. In a certain section, the only possible
values are NULL, 0,1,and 2. I need to be able to detect these NULL's and
be
able to have them counted. For example, in a frequency table. How can I
accomplish this?
Thanks in advance for the help.
--
Jason Thibodeau
[[alternative HTML version deleted]]
______________________________________________
R-help at r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.