Error in aggregate.data.frame : arguments must have same length

10
votes

I keep getting this error and I'm not quite sure what it means. All of my variable names are consistent and there are no typos. Am I missing something here?

The code 

datNewagg <- aggregate (dataNew, by = list('x', 'y', 'z', 'a', 'ab'), 
                                                             FUN = mean)

Produces the error

  Error in aggregate.data.frame(datNew, by = list("x", "y",  : 
  arguments must have same length
5
raggregate
Can you dput the exact datafame? – user2600629
Can you show the aggregate call, as it mat be incorrectly specified. ty – user20650
You get a similar error with aggregate(mtcars, list("am"), mean). But if you specify it like aggregate(mtcars, list(mtcars$am), mean) or aggregate(. ~ am , mean, data=mtcars) everything is okay – user20650
datNewagg <- aggregate (dataNew, by = list('x', 'y', 'z', 'a', 'ab'), FUN = mean) – RHatesMe
ok, have a look at the comment above on specifying aggregate function. . Try datNewagg <- aggregate (. ~ x + y + z + a + ab), FUN = mean, data=dataNew) or datNewagg <- with(dataNew, aggregate (dataNew, by = list(x, y, z, a, ab), FUN = mean)) – user20650

5 Answers

13
votes

Assuming it's not a typo (the data frame is called dataNew in your call but datNew in the error), are x, y, z, a and ab the names of columns in dataNew?

Some functions, like subset, will allow you to specify column names of the object they're working on directly. The aggregate function doesn't, so any columns of dataNew listed in the by argument need to specifically referred to as such. Try this:

datNewagg <- aggregate(dataNew,
    by = list(
        x = dataNew$x,
        y = dataNew$y,
        z = dataNew$z,
        a = dataNew$a,
        ab = dataNew$ab),
    FUN = mean)
9
votes

I used get this error.
The simple solution to remove this error is to write all the variables along with their dataset name like "ds_name$var_name".
I'm not sure what is the dataset name is your case, so I'll give you another similar example.

curYearRev <-aggregate(hr$Year.Total, by = list(hr$Hospital_ID,hr$District_ID,hr$Instrument_ID) , FUN = sum)

Here, "hr" is the dataset name and "Year.Total", "Hospital_ID", "District_ID", "Instrument_ID" are the variables in "hr" dataset.

Writing aggregate functions in this way will never give you any errors again.

1
votes

Check class(dataNew). If it's not a data.frame, this dataNew <- data.frame(dataNew) before aggregation should solve the error or

datNewagg <- aggregate (data.frame(dataNew), by = list('x', 'y', 'z', 'a', 'ab'), 
                                                         FUN = mean)
1
votes

When you use with(...,aggregate(...)) don't put your column names in quotes.

0
votes

Using data.frame as by argument works for me try this:

datNewagg <- aggregate (dataNew, by = dataNew[c('x', 'y', 'z', 'a', 'ab')],                                                             FUN = mean)

I mean don't give the by argument, just the name of the arguments, give a data.frame with columns as these arguments