Question

Hi I have a utility function I’ve put together to insert rows into a dataframe below. If I was writing out the formula by hand I would put something like

newframe=rbind(oldframe[1:rownum,],row_to_insert=row_to_insert,oldframe[(rownum+1:nrow(oldframe),] to name row_to_insert. Could someone tell me how to do this in a function?

Thanks

insertrows=function (x, y, rownum) 
{
    newframe = rbind(y[1:rownum, ], x, y[(rownum + 1):nrow(y), 
        ])
    return(data.frame(newframe))
}

MWE of some underlying data added below

financials=data.frame(sales=c(100,150,200,250),some.direct.costs=c(25,30,35,40),other.direct.costs=c(15,25,25,35),indirect.costs=c(40,45,45,50))

oldframe=t(financials)
colnames(oldframe)=make.names(seq(2000,2003,1))

total.direct.costs=oldframe['some.direct.costs',]+oldframe['other.direct.costs',]
newframe=total.direct.costs

n=rownum=3
oldframe=insertrows(total.direct.costs=newframe,oldframe,n)

Answer 1

Try this modified function:

insertrows <- function (x, oldframe, rownum) 
{
  newframe <- rbind(oldframe, x)
  rownames(newframe) <- c(rownames(oldframe),  deparse(substitute(x)))
  return(newframe[c(seq(n), nrow(oldframe) + 1, seq(n + 1, nrow(oldframe))), ])
}

Now, the name of the object which is passed as argument x will be used as the rowname of the new row (deparse(substitute(x))). The old rownames are kept. Furthermore, the ordering of the rows is now more efficient.

Run the function:

insertrows(total.direct.costs, oldframe, 3)

The output:

                   [,1] [,2] [,3] [,4]
sales               100  150  200  250
some.direct.costs    25   30   35   40
other.direct.costs   15   25   25   35
total.direct.costs   40   55   60   75
indirect.costs       40   45   45   50