How to split a string on first number only

So i have a dataset with street adresses, they are formatted very differently. For example:

d <- c("street1234", "Street 423", "Long Street 12-14", "Road 18A", "Road 12 - 15", "Road 1/2")

From this I want to create two columns. 1. X: with the street address and 2. Y: with the number + everything that follows. Like this:

X           Y
Street      1234
Street      423
Long Street 12-14
Road        18A
Road        12 - 15
Road        1/2

Until now I have tried strsplit and followed some similar questions here , for example: strsplit(d, split = "(?<=[a-zA-Z])(?=[0-9])", perl = T)). I just can't seem to find the correct regular expression.

Any help is highly appreciated. Thank you in advance!

There may be whitespace between the letter and a digit, so add \s* (zero or more whitespace symbols) between the lookarounds:

> strsplit(d, split = "(?<=[a-zA-Z])\\s*(?=[0-9])", perl = TRUE)
[[1]]
[1] "street" "1234"  

[[2]]
[1] "Street" "423"   

[[3]]
[1] "Long Street" "12-14"      

[[4]]
[1] "Road" "18A" 

[[5]]
[1] "Road"    "12 - 15"

[[6]]
[1] "Road" "1/2"

And if you want to create columns based on that, you might leverage the separate from tidyr package :

> library(tidyr)
> separate(data.frame(A = d), col = "A" , into = c("X", "Y"), sep = "(?<=[a-zA-Z])\\s*(?=[0-9])")
            X       Y
1      street    1234
2      Street     423
3 Long Street   12-14
4        Road     18A
5        Road 12 - 15
6        Road     1/2

This will also work:

do.call(rbind,strsplit(sub('([[:alpha:]]+)\\s*([[:digit:]]+)', '\\1$\\2', d), split='\\$'))
#     [,1]          [,2]     
#[1,] "street"      "1234"   
#[2,] "Street"      "423"    
#[3,] "Long Street" "12-14"  
#[4,] "Road"        "18A"    
#[5,] "Road"        "12 - 15"
#[6,] "Road"        "1/2"

A non-regex approach using str_locate from stringr to locate the first digit in the string and then split based on that location, i.e.

library(stringr)

ind <- str_locate(d, '[0-9]+')[,1]
setNames(data.frame(do.call(rbind, Map(function(x, y) 
          trimws(substring(x, seq(1, nchar(x), y-1), seq(y-1, nchar(x), nchar(x)-y+1))), 
                                                             d, ind)))[,1:2]), c('X', 'Y'))

#            X       Y
#1      street    1234
#2      Street     423
#3 Long Street   12-14
#4        Road     18A
#5        Road 12 - 15
#6        Road     1/2

NOTE that you receive a (harmless) warning which is a result of the split at "Road 12 - 15" string which gives [1] "Road" "12 - 15" ""

We can use read.csv with sub from base R

read.csv(text=sub("^([A-Za-z ]+)\\s*([0-9]+.*)", "\\1,\\2", d), 
        header=FALSE, col.names = c("X", "Y"), stringsAsFactors=FALSE)
#             X       Y
#1       street    1234
#2      Street      423
#3 Long Street    12-14
#4        Road      18A
#5        Road  12 - 15
#6        Road      1/2

来源：https://stackoverflow.com/questions/42133934/how-to-split-a-string-on-first-number-only

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regex

strsplit