I wish to evaluate a vector of strings containing arithmetic expressions -- "1+2", "5*6", etc.
I know that I can parse a single string into an expression and then evaluate it as in eval(parse(text="1+2"))
.
However, I would prefer to evaluate the vector without using a for loop.
foo <- c("1+2","3+4","5*6","7/8") # I want to evaluate this and return c(3,7,30,0.875)
eval(parse(text=foo[1])) # correctly returns 3, so how do I vectorize the evaluation?
eval(sapply(foo, function(x) parse(text=x))) # wrong! evaluates only last element
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