r - Simultaneously subsetting and operating on a specific column of a data frame -

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let's have data.frame df

df<-data.frame(a=1:5,b=101:105,c=201:205)

can call subset of data while simultaneously performing kind of modification (e.g., arithmetic) 1 of columns (or rows) on fly?

for example, if want return first , second column of df return log of column 1 values. there notation modify df[,1:2] produce following on fly?:

              b >1  0.0000000 101 >2  0.6931472 102 >3  1.0986123 103 >4  1.3862944 104 >5  1.6094379 105

this example within()

within(df[1:2], <- log(a)) #             b # 1 0.0000000 101 # 2 0.6931472 102 # 3 1.0986123 103 # 4 1.3862944 104 # 5 1.6094379 105

or if prefer not have <- in call, can use brackets

within(df[1:2], { = log(a) })

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