13 lines
341 B
R
13 lines
341 B
R
d <- data.frame(a=c(2,4,6), b = c(5,7,9))
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also <- c(1, 0, 2)
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with(d, mean(b - a + also)) #returns 4
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## with() is built in, but you might have implemented it like this:
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with.impl <- function(env, expr) {
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env <- as.environment(env)
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parent.env(env) <- parent.frame()
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eval(substitute(expr), envir=env)
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}
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with.impl(d, mean(b - a + also))
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