I'm using the quanteda package to produce a sparse matrix of word frequency counts. I want to make a change so that the output is bonary so simply 1 or 0, is the word present or not but i'm not sure how to do this with a sparse matrix.
install.packages(quanteda)
Example matrix
trainingset <- as.dfm(matrix(c(1, 2, 0, 0, 0, 0,
0, 2, 0, 0, 1, 0,
0, 1, 0, 1, 0, 0,
0, 1, 1, 0, 0, 1,
0, 3, 1, 0, 0, 1),
ncol=6, nrow=5, byrow=TRUE,
dimnames = list(docs = paste("d", 1:5, sep = ""),
features = c("Beijing", "Chinese", "Japan", "Macao",
"Shanghai", "Tokyo"))))
If you have a look at str(trainingset) you can see the slots of the matrix. As with sparse matrices the x slot holds the data, so you can change this to binary using
trainingset@x <- as.numeric(trainingset@x > 0)
Document-feature matrix of: 5 documents, 6 features (60% sparse).
5 x 6 sparse Matrix of class "dfmSparse"
features
docs Beijing Chinese Japan Macao Shanghai Tokyo
d1 1 1 0 0 0 0
d2 0 1 0 0 1 0
d3 0 1 0 1 0 0
d4 0 1 1 0 0 1
d5 0 1 1 0 0 1