library(sfsmisc)
expo <- -3:4
stopifnot(exprs = {
    all.equal(pretty10exp(10^expo, drop.1=TRUE, sub10 = c(-2, 2)),
              expression(10^-3, 0.01, 0.1, 1, 10, 100, 10^3, 10^4))

    identical(pretty10exp(10^expo, drop.1=TRUE, sub10 = c(-2, 2), lab.type="latex"),
              c("$10^{-3}$", "0.01", "0.1", "1", "10", "100",
                "$10^{3}$", "$10^{4}$"))
    ## gave exponential format for "latex" case.
})