如何在 R 中将单个字符向量转换为数字？

Question

one column of my dataset looks like below;

"[3, 4, 5, 6]"

and I want to split every single value of this vector-like below as numeric;

3, 4, 5, 6 

What can I do?

Thank you for your answers.

Answer 1

Remove the brackets and split the string using the commas. strsplit() returns a list. You want a vector, so let us unlist() it and convert it to numerics.

x <- "[3, 4, 5, 6]"
x <- gsub("\\[|\\]","", x)
y <- as.numeric(unlist(strsplit(x, ",", fixed=TRUE)))
y
#> [1] 3 4 5 6

^{Created on 2021-05-01 by the reprex package (v2.0.0)}

Answer 2

For this vector

x = "[3, 4, 5, 6]"

find all matches of a sequence of 1 or more digits and extract the matches from the original location

match = gregexpr("[[:digit:]]+", x)
values = regmatches(x, match)

This is a list of character values; coerce to integer, eg, allowing x to be more than length 1

lapply(values, as.integer)