R：在data.frame字段中拆分多个值/关键字对

Question

I've got a data.frame that contains a field like this:

:6:Description_C
:3:Description_A:2:Description_B:1:Description_C
:2:Description_C:1:Description_B:1:Description_A:1:Description_D:1:Description_E
:3:Description_B:3:Description_A

The number in front, surrounded by colons, is the number of times, out of a total of 6, which the Description is seen in that entry in the data.frame. If there is a :6:Description_X means that all 6 counts go for that description, if not it's split into different counts, one next to each other.

I would like to turn this field into a key/value hash of number of counts for each description, so that I can then do a barplot of the total proportions for all counts, but also in a way that I can plot these proportions in combination with the other factors in the data.frame.

EDIT: looking a bit at the doc for colsplit, probably what people will tell me is that I need a new column for each description, since I only have about 8 descriptions in total. Still, haven't figured out how to do it.

How can I do that in R?

Answer 1

I'm not sure what structure you wanted for the "key:value hash" but this will extract the strings and their associated numeric reps:

inp <- readLines(textConnection(
 ":6:Description_C
 :3:Description_A:2:Description_B:1:Description_C
 :2:Description_C:1:Description_B:1:Description_A:1:Description_D:1:Description_E
 :3:Description_B:3:Description_A")
        )
 inp2 <- sapply( strsplit(inp, ":"), "[", -1) # drop the leading empty strings
 reps <-  lapply(inp2, function(x) as.numeric(x[ seq( 1, length(x) , by=2)]))
 values <- lapply(inp2, function(x) x[ seq( 2, length(x) , by=2)])

lapply(reps, barplot) # Probably needs to work but this demonstrates feasibility