[R] Quick recode of -999 to NA in R

[Gavin Simpson]

On Wed, 2011-03-30 at 08:15 -0500, Christopher Desjardins wrote:
> Hi,
> I am trying to write a loop to recode my data from -999 to NA in R. What's
> the most efficient way to do this? Below is what I'm presently doing, which
> is inefficient. Thanks,
> Chris
> 
> 
>    dat0 <- read.table("time1.dat")

dat0 <- read.table("time1.dat", na.strings = c("NA","-999"))

would seem the easiest option.

Do read ?read.table for details.

HTH

G

> colnames(dat0) <- c("e1dq", "e1arcp", "e1dev", "s1prcp", "s1nrcp", "s1ints",
> "a1gpar", "a1pias", "a1devt")
> 
> dat0[dat0$e1dq==-999.00000000,"e1dq"] <- NA
> 
> dat0[dat0$e1arcp==-999.00000000,"e1arcp"] <- NA
> 
> dat0[dat0$e1dev==-999.00000000,"e1dev"] <- NA
> 
> dat0[dat0$s1prcp==-999.00000000,"s1prcp"] <- NA
> 
> dat0[dat0$s1nrcp==-999.00000000,"s1nrcp"] <- NA
> 
> dat0[dat0$s1ints==-999.00000000,"s1ints"] <- NA
> 
> dat0[dat0$a1gpar==-999.00000000,"a1gpar"] <- NA
> 
> dat0[dat0$a1pias==-999.00000000,"a1pias"] <- NA
> 
> dat0[dat0$a1devt==-999.00000000,"a1devt"] <- NA
> 
> 	[[alternative HTML version deleted]]
> 
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