how to extract number beside specific string in a cell? - r

Question

I would like to extract number information in cells which is located beside specific string. My data looks like this.
item stock
PRE 24GUSSETX4SX15G 200
PLS 12KLRX10SX15G 200
ADU 24SBX200ML 200
NIS 18BNDX40SX11G 200
REF 500GX12BTL 200
i want to extract the numbers which located besides string 'GUSSET','KLR','SB','BND' and 'BTL'. I want to use this number to do multiplication with the stock. For example like this.
item stock pcs total
PRE 24GUSSETX4SX15G 200 24 4800
PLS 12KLRX10SX15G 200 12 2400
ADU 24SBX200ML 200 24 4800
NIS 18BNDX40SX11G 200 18 3600
REF 500GX12BTL 200 12 2400
anyone know how to extract the numbers? thanks very much in advance

Answer 1

One way using base R, is to use sub to extract numbers besides those groups and multiply them with stock to get total.
df$pcs <- as.numeric(sub(".*?(\\d+)(GUSSET|KLR|SB|BND|BTL).*", "\\1", df$item))
df$total <- df$stock * df$pcs
df
# item stock pcs total
#PRE 24GUSSETX4SX15G 200 24 4800
#PLS 12KLRX10SX15G 200 12 2400
#ADU 24SBX200ML 200 24 4800
#NIS 18BNDX40SX11G 200 18 3600
#REF 500GX12BTL 200 12 2400
Or everything in one pipe
library(dplyr)
df %>%
mutate(pcs = as.numeric(sub(".*?(\\d+)(GUSSET|KLR|SB|BND|BTL).*", "\\1", item)),
total = stock * pcs)

Answer 2

We can do this in tidyverse
library(tidyverse)
df %>%
mutate(pcs = as.numeric(str_extract(item, "(\\d+)(?=(GUSSET|KLR|SB|BND|BTL))")),
total = pcs * stock)
# item stock pcs total
#1 PRE 24GUSSETX4SX15G 200 24 4800
#2 PLS 12KLRX10SX15G 200 12 2400
#3 ADU 24SBX200ML 200 24 4800
#4 NIS 18BNDX40SX11G 200 18 3600
#5 REF 500GX12BTL 200 12 2400
data
df <- structure(list(item = c("PRE 24GUSSETX4SX15G", "PLS 12KLRX10SX15G",
"ADU 24SBX200ML", "NIS 18BNDX40SX11G", "REF 500GX12BTL"), stock = c(200L,
200L, 200L, 200L, 200L)), class = "data.frame", row.names = c(NA,
-5L))