R change $xxx.xx to xxx.xx for both positive and negative numbers but don't round

Question

I have a df where columns 2 and beyond are dollar amounts such as $1004.23, ($1482.40), $2423.94 etc. Similar to the example below:

> df
  id   desc    price
         


        

Answer 1

This is similar to Matt's answer, but it is vectorized (no loop over the rows needed). It further combines Procrastinatus Maximus' approach to treat several columns, and it also works if the values are originally stored as factors:

df1[3:ncol(df1)] <- apply(df1[3:ncol(df1)], 2, function(x) 
                         as.numeric(gsub("(", "-", gsub(")", "", gsub("$", "",
                         as.character(x), fixed=TRUE)), fixed=TRUE)))
#> df1
#  id   desc price price2
#1  0  apple  1.00  -5.90
#2  1 banana -2.25   2.39
#3  2 grapes  1.97  -0.95

data

df1 <- structure(list(id = 0:2, desc = structure(1:3, .Label = c("apple", 
         "banana", "grapes"), class = "factor"), price = structure(c(1L, 3L, 2L),
         .Label = c("$1.00", "$1.97", "($2.25)"), class = "factor"), 
         price2 = structure(c(3L, 2L, 1L), 
         .Label = c("($0.95)", "$2.39", "($5.90"),
         class = "factor")), .Names = c("id", "desc", "price", "price2"),
         class = "data.frame", row.names = c("1", "2", "3"))