Linear Model "NA" Value Test
On Sep 21, 2009, at 4:38 PM, Douglas M. Hultstrand wrote:
Hello,
I am deriving near real-time liner relationships based on 5-min
precipitation data, sometimes the non-qced data result in a slope of
NA. I
am trying to read the coefficient (in this example x) to see if it
is equal
to NA, if it is equal to NA assign it a value of 1. I am having
trouble
with the if statement not recognizing the coefficient or "NA" value
in the
test.
Any thoughts, I supplied a really basic example below.
Thank you,
Doug
#####################
###### Example ######
#####################
x=c(1,1,1)
y=c(1,1,1)
fit <- lm(y~x) fit
Call:
lm(formula = y ~ x)
Coefficients:
(Intercept) x
1 NA
coef <- coef(fit) fit$coef[[2]]
[1] NA
if("fit$coef[[2]]" == "NA") {.cw = 1}
. That would test for equality to the string composed of "N" and "A" but not for NA. (Nothing "equals" NA. ) ?is.na
-- --------------------------------- Douglas M. Hultstrand, MS Senior Hydrometeorologist Metstat, Inc. Windsor, Colorado voice: 970.686.1253 email: dmhultst at metstat.com web: http://www.metstat.com
______________________________________________ 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.
David Winsemius, MD Heritage Laboratories West Hartford, CT