Add failing test

tests/testthat/test-inpar-saem.R

@@ -0,0 +1,46 @@
+test_that("fix parameter saem (#445)", {
+
+  theo_sd2 <- nlmixr2data::theo_sd
+
+  theo_sd2$lwt<-log(theo_sd2$WT/70)
+
+  # The basic model consists of an ini block that has initial estimates
+  one.compartment <- function() {
+    ini({
+      tka <- log(1.57); label("Ka")
+      tcl <- log(2.72); label("Cl")
+      tv <- log(31.5); label("V")
+      covwt<- fix(0.01)
+      eta.ka ~ 0.6
+      eta.cl ~ 0.3
+      eta.v ~ 0.1
+      add.sd <- 0.7
+    })
+    model({
+      ka <- exp(tka + eta.ka)
+      cl <- exp(tcl + eta.cl + covwt*lwt)
+      v <- exp(tv + eta.v)
+      d/dt(depot) <- -ka * depot
+      d/dt(center) <- ka * depot - cl / v * center
+      cp <- center / v
+      cp ~ add(add.sd)
+    })
+  }
+
+  fit0 <- nlmixr2(one.compartment, theo_sd2,  est="saem",
+                  saemControl(print=0,seed = 1234, nBurn = 1, nEm = 1,
+                              calcTables = FALSE))
+
+  fit1 <- nlmixr2(one.compartment %>% ini(covwt=fix(100)), theo_sd2,  est="saem",
+                  saemControl(print=0,seed = 1234, nBurn = 1, nEm = 1,
+                              calcTables = FALSE))
+
+  theta0 <- fit0$theta
+  theta0 <- theta0[names(theta0) != "covwt"]
+
+  theta1 <- fit1$theta
+  theta1 <- theta1[names(theta1) != "covwt"]
+
+  expect_true(!all(theta1 == theta0))
+
+})