man/examples/merge.edsurvey.data.frame.R

In EdSurvey: Analysis of NCES Education Survey and Assessment Data

\dontrun{
# read in NAEP primer data
sdf <- readNAEP(system.file("extdata/data", "M36NT2PM.dat", package = "NAEPprimer"))
lsdf <- getData(data=sdf, varnames=c("dsex", "b017451"), addAttributes = TRUE)
df <- data.frame(dsex = c("Male","Female"), dsex2 = c("Boy","Girl"))

#merging an edsurvey.data.frame with a data.frame/light.edsurvey.data.frame
#returns an edsurvey.data.frame object
sdf2 <- merge(sdf, df, by = "dsex")
table(sdf2$dsex2)

# merging a light.edsurvey.data.frame with a data.frame
# returns a light.edsurvey.data.frame object
merged_lsdf <- merge(lsdf,df, by = "dsex")
class(merged_lsdf) #  "light.edsurvey.data.frame" "data.frame"
head(merged_lsdf) # shows merge results

# merging behaves similarly to base::merge
df2 <- data.frame(dsex = c("Male","Female"), b017451 = c(1,2))
merged_lsdf2 <- merge(lsdf,df2, by = "dsex")
names(merged_lsdf2) # "dsex"      "b017451.x" "b017451.y"
head(merged_lsdf2) # shows merge results
}