melt.data.frame {reshape2} | R Documentation |
You need to tell melt which of your variables are id
variables, and which are measured variables. If you only
supply one of id.vars
and measure.vars
,
melt will assume the remainder of the variables in the
data set belong to the other. If you supply neither, melt
will assume factor and character variables are id
variables, and all others are measured.
## S3 method for class 'data.frame' melt(data, id.vars, measure.vars, variable.name = "variable", ..., na.rm = FALSE, value.name = "value")
data |
data frame to melt |
id.vars |
vector of id variables. Can be integer (variable position) or string (variable name)If blank, will use all non-measured variables. |
measure.vars |
vector of measured variables. Can be integer (variable position) or string (variable name)If blank, will use all non id.vars |
variable.name |
name of variable used to store measured variable names |
value.name |
name of variable used to store values |
na.rm |
Should NA values be removed from the data set? This will convert explicit missings to implicit missings. |
... |
further arguments passed to or from other methods. |
names(airquality) <- tolower(names(airquality)) melt(airquality, id=c("month", "day")) names(ChickWeight) <- tolower(names(ChickWeight)) melt(ChickWeight, id=2:4)