Not sure, but maybe check the name of the column(s) you are retrieving
you may get a NULL value if the column name is misspelled
R example:
## --------------------------------------
df <- data.frame(
"Publication" = 1991:2000,
"Reference" = LETTERS[1:10] )
df[ 2, "References" ]
# NULL
## Notice the extra 's'
## --------------------------------------
If that does not fix your error, can you send us the output from
head(x)
# and
dput(head(x))
So we have an idea what your table looks like?
All the best
Julien
________________________________________
From: [email protected] [[email protected]] On Behalf Of
Sri krishna Devarayalu Balanagu [[email protected]]
Sent: 01 August 2012 08:58
To: [email protected]
Subject: [R] Why the result is coming as NULL?
Why the result is coming as NULL. Can anyone help. I want to find the outliers
for a reference
setwd("D:/AZ")
library("RODBC")
cdb_cnct <- odbcConnectExcel("Book1.xls")
cdb_frame <- sqlFetch(cdb_cnct, "Sheet1")
odbcClose(cdb_cnct)
rm(cdb_cnct)
x<- cdb_frame$Publication >=1990 & cdb_frame$Publication <=2012
invalid <- cdb_frame[!x, c("Reference")]
invalid
________________________________
Notice: The information contained in this electronic mail message is intended
only for the use of the designated recipient. This message is privileged and
confidential. and the property of GVK BIO or its affiliates and subsidiaries.
If the reader of this message is not the intended recipient or an agent
responsible for delivering it to the intended recipient, you are hereby
notified that you have received this message in error and that any review,
dissemination, distribution, or copying of this message is strictly prohibited.
If you have received this communication in error, please notify us immediately
by telephone +91-40-66929999<tel:%2B91-40-66929999> and destroy any and all
copies of this message in your possession (whether hard copies or
electronically stored copies).
______________________________________________
[email protected] 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.