Merge pull request #27 from Spatiotemporal-Exposures-and-Toxicology/u…

…nit-test

Unit test

R/obj_hill.R

@@ -5,7 +5,7 @@
 #' @param resp response
 #'
 #' @return value
-obj_hill <- function (par, log10_conc, resp) {
+obj_hill <- function(par, log10_conc, resp) {
 
   tp       <- par[1]  # top asymptote
   log10_ga <- par[2]  # log10(AC50)

tests/testthat/test-obj_hill.R

@@ -0,0 +1,50 @@
+# Testing the obj-hill functions
+test_that("2 and 3 parameter models give accurate likelihood", {
+
+## hill function for simulation
+  hill_fun <- function(x, alpha, beta, theta){
+    alpha / (1 + 10^(beta * (theta - x)))
+  }
+
+## Creating regular parameters
+  tp <- 1
+  log10_ga <- 1
+  gw <- 2
+  err <- 1
+
+## 2-parameter model
+
+  #simulate dose-response
+  params2 <- c(tp, log10_ga, err)
+  log10_conc <- seq(0.1,10,length.out = 50)
+  resp <- hill_fun(log10_conc, tp, log10_ga, gw)
+
+  # 2 parameter hill model expectation
+  val <- obj_hill(params2, log10_conc, resp)
+  expect_equal(val, -100.201, tolerance = 0.001)
+
+## 3-parameter model
+
+  # 3 parameter hill model expectation
+  params3 <- c(tp, log10_ga, gw, err)
+  val <- obj_hill(params3, log10_conc, resp)
+  expect_equal(val, -99.23463, tolerance = 0.001)
+
+
+#### Edge Tests
+
+# Really tiny parameter values
+
+  #simulate dose-response
+  params_tiny <- c(1e-10, 1e-10, 1e-10, 1e-10)
+
+  expect_no_warning(obj_hill(params_tiny, log10_conc, resp))
+
+
+  # Really large parameter values
+
+  #simulate dose-response
+  params_large <- c(1e10, 1e10, 1e10, 1e10)
+
+  expect_no_warning(obj_hill(params_tiny, log10_conc, resp))
+})