How do I create 1s and 0s matrix from 2 vectors of strings?

Question

I'm creating a matrix of 1s and 0s. It is 1 if a word is part of a string, 0 otherwise.

For example the expected matrix would be something as follow:

                           white hanging heart holder black suitcase
white hanging heart holder     1       1     1      1     0        0
black suitcase                 0       0     0      0     1        1

What I have at disposal are the 2 vectors:

Itemsvector = c("white hanging heart holder","black suitcase", ...)
Wordsvector = c("white","hanging","heart","holder","black", "suitcase",...)

I'm toying around the use of %in% operator

strsplit(Itemsvector[1], split = ' ')[[1]] %in% Wordsvector

Also

grepl(Wordsvector[1], Itemsvector)

Which does give me the TRUE and FALSE value, though I'm at lost to map this set of values to the whole matrix grid.

Answer 1

We can do this much easier with table after splitting the 'Itemsvector' into a list of vector s, stack it to a data.frame and use the table

table(stack(setNames(strsplit(Itemsvector, " "), Itemsvector))[2:1])
#                             values
#ind                          black hanging heart holder suitcase white
#  white hanging heart holder     0       1     1      1        0     1
#  black suitcase                 1       0     0      0        1     0

---

Or with mtabulate

library(qdapTools)
mtabulate(setNames(strsplit(Itemsvector, " "), Itemsvector))

Answer 2

You could try using double sapply and since you already have Wordsvector to search for no need to split Itemsvector again. We can find if a particular word is present or not in particular Itemsvector using grepl and for extra precaution we add word boundaries so that it doesn't match "white" with " whites" .

+(t(sapply(Itemsvector, function(x) sapply(Wordsvector, function(y) 
                                  grepl(paste0("\\b",y, "\\b"), x)))))

#                           white hanging heart holder black suitcase
#white hanging heart holder     1       1     1      1     0        0
#black suitcase                 0       0     0      0     1        1

data

Itemsvector = c("white hanging heart holder","black suitcase")
Wordsvector = c("white","hanging","heart","holder","black", "suitcase")