Skip to content
Prev 163913 / 398506 Next

adding rows as arithmatic calculation on original rows

Gabor Grothendieck 
Here is a solution using sqldf



library(sqldf)

DF2 <-
structure(list(myID = structure(1:4, .Label = c("a", "b", "c",
"d"), class = "factor"), myType = structure(c(2L, 2L, 1L, 1L), .Label
= c("Double",
"Single"), class = "factor"), myNum1 = c(10, 15, 22, 4), myNum2 = c(11,
25, 33, 6), myNum3 = c(12, 35, 44, 8)), .Names = c("myID", "myType",
"myNum1", "myNum2", "myNum3"), row.names = c(NA, -4L), class = "data.frame")

sqldf("select 1 TotalLevel, '+' myID, myType, avg(myNum1) myNum1,
avg(myNum2) myNum2, avg(myNum3) myNum3
  from DF2
  group by myType
union
  select 0 TotalLevel, *
     from DF2
order by myType, TotalLevel, myID",
method = "raw")[-1]

The output is (display in fixed font):

  myID myType myNum1 myNum2 myNum3
1    c Double   22.0   33.0   44.0
2    d Double    4.0    6.0    8.0
3    + Double   13.0   19.5   26.0
4    a Single   10.0   11.0   12.0
5    b Single   15.0   25.0   35.0
6    + Single   12.5   18.0   23.5
On Fri, Dec 5, 2008 at 3:21 PM, Ferry <fmi.mlist at gmail.com> wrote:

Thread (6 messages)

Ferry adding rows as arithmatic calculation on original rows Dec 5 jim holtman adding rows as arithmatic calculation on original rows Dec 5 Ferry adding rows as arithmatic calculation on original rows Dec 5 Gabor Grothendieck adding rows as arithmatic calculation on original rows Dec 5 eric adding rows as arithmatic calculation on original rows Dec 5 Ferry adding rows as arithmatic calculation on original rows Dec 5