[R] Excluding all missing values with dcast ("reshape2" package)

[Michael.Laviolette at dhhs.state.nh.us]

Thanks for the response. It turns out this will work if the data include no
other variables with missings; unfortunately, that was the case. I was
successful using xtabs with the extra step of converting the returned table
to a data frame. Thanks again!

-M.L.

Hi,
?na.omit()
dat1<-read.table(text="
Tool Step_Number
A 1
A 2
A 3
A 3
B 1
B 2
B 2
B 3
B NA
NA 3
",sep="",header=TRUE,stringsAsFactors=FALSE)
 dcast(na.omit(dat1),Tool~Step_Number,length)
#Using Step_Number as value column: use value.var to override.
 # Tool 1 2 3
#1    A 1 1 2
#2    B 1 2 1

A.K.





----- Original Message -----

Hello--I'm doing a simple crosstab using dcast:

rawfreq <- dcast(nh11brfs, race3~CHCCOPD, length)

with the results

               race3 Yes   No NA
1 White non-Hispanic 446 5473 21
2 Other non-Hispanic  29  211  0
3           Hispanic   6   81  1
4               <NA>  10   83  1

How would I modify this call to exclude all missing values; that is, to
obtain

               race3 Yes   No
1 White non-Hispanic 446 5473
2 Other non-Hispanic  29  211
3           Hispanic   6   81

Apologies if this has come up before, and thanks.

-M.L.