How to extract multi-word units from a column using R?

Question

my data looks like this:

Topic	Measure
climate change	reduce emissions
pandemic	vaccination
charity	call for donations

Now I would like to extract all multi-word units (MWU) within one column, ie:

topic_mwu<-c("climate change")

measure_mwu<-c("reduce emission","call for donations")

Is there a function in R to extract these MWU automatically? Basically I only have to identify those entries including at least one whitespace, so I am thinking of an RegEx - hack..

I would very much appreciate your help!

Answer 1

The code below should work:

#your dataframe
dt <- matrix(c("reduce emission", "call for donations", "pandemic", "climate change", "donations", "charity"), ncol =2)

#make it a vector
dt <- as.vector(dt)

#if the table is very big, you can do unique() to remove duplicates
dt <- unique(dt)

#get the MWU
dt[unlist(lapply(strsplit(dt,split = " "), length)) > 1]

Is this what you were looking for?