How to convert all column data type to numeric and character dynamically?

Question

I convert my columns data type manually:

data[,\'particles\'] <- as.numeric(as.character(data[,\'particles\']))

This not ideal as the da

Answer 1

Use lapply:

cols <- c("particles", "nox", ...)

data[,cols] <- lapply(data[,cols], function(x) as.numeric(as.character(x)))