Zero position matters: one selection problem-CodePudding

I'd like to match some results by a rule. In my case:

original.names <- c("TL-13","TL-09","TL-12","TL-19A","TL-11","TL-20","TL-16",
"TL-15","TL-14","TL-10","TL-18","TL-19","TL-08A","TL-07A","TL-17A","TL-17",
"TL-21","TL-09A","TL-22","TL-08","TL-05","TL-03","TL-06","TL-07","TL-02","TL-04","TL-01") 

selection <- c(1)

which(original.names==selection)
#integer(0)

But in my case TL-01 is 1. If I make which(gsub("TL-|0","",original.names)==selection), it doesn't work too because 10 and 01 are different and gsub turns equal. Sometimes I have something like 8A (number-alphabetic) and I need to consider this situation too.

Please any help with it?

CodePudding user response：

Similar approach to @benson23 but capturing the required value instead of removing.

which(as.integer(sub('TL-(\\d ).*', '\\1', original.names)) == selection)
#[1] 27

This captures the numbers that occurs after TL-, converts it to integer and compares it with selection.

CodePudding user response：

You'll need to remove all character strings from your original.names, then convert it to integer type before you can do a comparison.

original.names <- c("TL-13","TL-09","TL-12","TL-19A","TL-11","TL-20","TL-16",
                    "TL-15","TL-14","TL-10","TL-18","TL-19","TL-08A","TL-07A","TL-17A","TL-17",
                    "TL-21","TL-09A","TL-22","TL-08","TL-05","TL-03","TL-06","TL-07","TL-02","TL-04","TL-01") 

selection <- 1

which(as.integer(gsub("\\D", "", original.names)) == selection)
[1] 27

CodePudding user response：

Here's another option using parse_number, although we have to wrap with abs as readr will take the dash to be a negative.

library(readr)

which(abs(parse_number(original.names)) == selection)

# [1] 27

CodePudding user response：

We could use str_pad:

library(stringr)

which(str_match(original.names, '\\d ')== 
        str_pad(selection, 2, pad = "0"))

[1] 27

CodePudding user response：

You can remove everything before - and also the following 0.

selection <- 1
which(sub("^.*-0*", "", original.names) %in% sub("^0*", "", selection))
#[1] 27

selection <- "8A"
which(sub("^.*-0*", "", original.names) %in% sub("^0*", "", selection))
#[1] 13

selection <- "01"
which(sub("^.*-0*", "", original.names) %in% sub("^0*", "", selection))
#[1] 27

selection <- c(1, "8A")
which(sub("^.*-0*", "", original.names) %in% sub("^0*", "", selection))
#[1] 13 27