search for: planttypetreatment

...sqrt(). - -- - -- - -- A further inconsistency is that the Math methods directly refuse to work on a data frame with non-numeric variables, whereas the Ops methods just go along and give warnings and NA's: > sqrt(CO2) Error in Math.data.frame(CO2) : non-numeric variable in data frame: PlantTypeTreatment > str( CO2 ^ 0.5 ) num [1:84, 1:5] NA NA NA NA NA NA NA NA NA NA ... - attr(*, "dimnames")=List of 2 ..$ : chr [1:84] "1" "2" "3" "4" ... ..$ : chr [1:5] "Plant" "Type" "Treatment" "conc" ... Warning...

Should arithmetic operations work on zero-column data.frames (returning a zero-column data.frame with the same number of rows as the data.frame argument(s))? Currently we get: > 1 + data.frame(row.names=c("A","B")) Error in data.frame(value, row.names = rn, check.names = FALSE, check.rows = FALSE) : row names supplied are of the wrong length >