library(testthat) test_that("tt_hourly_pp returns a numeric vector of length 24", { tmin <- 10 tmax <- 20 tmax_b <- 21 tmin_a <- 11 lat <- -27 doy <- 10 result <- tt_hourly_pp(tmin, tmax, tmax_b, tmin_a, lat, doy) expect_type(result, "double") # Ensure result is numeric expect_length(result, 24) # Ensure result has 24 hourly values }) test_that("tt_hourly_pp handles invalid inputs", { expect_error(tt_hourly_pp("ten", 20, 21, 11, -27, 10)) expect_error(tt_hourly_pp(10, 20, 21, 11, -100, 10)) expect_error(tt_hourly_pp(10, 20, 21, 11, -27, 400)) })