Re: [R] dataframe calculations based on certain values of a column

2014-03-27 Thread johannesradin...@gmail.com
calculations based on certain values of a column I believe this will generalize. But check carefully! Using your example (Excellent!), use ave(): with(df,ave(seq_along(var1),var2,FUN=function(i) var3[i]/var3[i][var1[i]==c])) [1] 0.500 1.000 1.000 0.833 0.333 1.000

[R] dataframe calculations based on certain values of a column

2014-03-26 Thread Johannes Radinger
Hi, I have data in a dataframe in following structure var1 - c(a,b,c,a,b,c,a,b,c) var2 - c(X,X,X,Y,Y,Y,Z,Z,Z) var3 - c(1,2,2,5,2,6,7,4,4) df - data.frame(var1,var2,var3) Now I'd like to calculate relative values of var3. This values should be relative to the base value (where var1=c) which is

Re: [R] dataframe calculations based on certain values of a column

2014-03-26 Thread Bert Gunter
I believe this will generalize. But check carefully! Using your example (Excellent!), use ave(): with(df,ave(seq_along(var1),var2,FUN=function(i) var3[i]/var3[i][var1[i]==c])) [1] 0.500 1.000 1.000 0.833 0.333 1.000 1.750 [8] 1.000 1.000 This is kind of a

Re: [R] dataframe calculations based on certain values of a column

2014-03-26 Thread Berend Hasselman
On 26-03-2014, at 17:09, Johannes Radinger johannesradin...@gmail.com wrote: Hi, I have data in a dataframe in following structure var1 - c(a,b,c,a,b,c,a,b,c) var2 - c(X,X,X,Y,Y,Y,Z,Z,Z) var3 - c(1,2,2,5,2,6,7,4,4) df - data.frame(var1,var2,var3) Now I'd like to calculate relative

Re: [R] dataframe calculations based on certain values of a column

2014-03-26 Thread Noah Marconi
dplyr's group_by and mutate can create those columns for you: var1 - c(a,b,c,a,b,c,a,b,c) var2 - c(X,X,X,Y,Y,Y,Z,Z,Z) var3 - c(1,2,2,5,2,6,7,4,4) df - data.frame(var1,var2,var3) dt - tbl_df(df) dt %.% group_by(var2) %.% mutate( div = var3[var1 == c], result_calc = var3/div )