A single column with many values separated by semicolon, R

Question

I have a column with 1000 rows. Each row has 5000 values all separated with semicolon. I like to turn this column into a matrix of 1000 x 5000 dimension. How can I do this in R?

Thanks, Aaron

You should provide a [reproducible example](http://stackoverflow.com/q/5963269/1217536) for people to work with. — gung - Reinstate Monica, Jun 20 '16 at 17:05
`library(splitstackshape); cSplit(df, 'V1', sep=";", type.convert=FALSE)` — Hack-R, Jun 20 '16 at 17:09

score 0 · Answer 1 · answered Jun 20 '16 at 17:16

0

as.numeric(strsplit(A[,1],";"))

if the data is in a dataframe or array

as.numeric(strsplit(A,";"))

if the data is a vector

answered Jun 20 '16 at 17:16

Rockbar

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score 0 · Answer 2 · answered Jun 20 '16 at 17:16

This would be one way to do it.

my_data <- data.frame(one_column = c("5;6;5;6;7", "6;5;3;2;5"))
my_data
        one
1 5;6;5;6;7
2 6;5;3;2;5

# split each row by a semicolon
my_list <- apply(my_data, 1, strsplit, split = ";")

# unlist and turn it into a matrix
my_matrix <- matrix(as.numeric(unlist(my_list)), nrow = nrow(my_data), 
                    ncol =length(my_list[[1]][[1]]), byrow = TRUE)
my_matrix
     [,1] [,2] [,3] [,4] [,5]
[1,]    5    6    5    6    7
[2,]    6    5    3    2    5

You could specify the number of rows and columns if you would like. Here I am assuming that you do indeed have 5000 values for each row.

if it worked please up vote the solution so that it is marked as answered. — mfidino, Jun 20 '16 at 17:39

score 0 · Answer 3 · answered Jun 20 '16 at 17:20

Let's start creating an example of this dataframe that contains 1 column with semicolon separated values:

d <- data.frame(col1 = paste0(runif(1000), ";", runif(1000), ";", runif(1000)), stringsAsFactors = F)

This is how the dataframe looks like:

head(d)
                                                    col1
1   0.20093023753725;0.399978927802294;0.404899704502895
2 0.424904063809663;0.0908958145882934;0.340853224741295
3  0.850118306931108;0.518901573261246;0.364027933450416
4 0.0212442732881755;0.760768163017929;0.146710442844778
5 0.0331723166164011;0.153021499980241;0.449281473178416
6 0.733110485365614;0.0544649658259004;0.663546974770725

The following 2 lines of code produce what you want:

library(stringr)

t <- str_split(d$col1, ";")
d2 <- do.call(rbind, t)

The first line produces a list where each element contains the split values. The second line binds them all together in a matrix.

A single column with many values separated by semicolon, R

3 Answers3