Warn if prediction outside fitted #285

R/predict.R

@@ -353,6 +353,20 @@ predict.sdmTMB <- function(object, newdata = NULL,
           "Did you miss specifying the argument `xy_cols` to match your data?",
           "The newer `make_mesh()` (vs. `make_spde()`) takes care of this for you."))
 
+    if (isFALSE(pop_pred) && !no_spatial) {
+      xy_orig <- object$data[,xy_cols]
+      xy_nd <- newdata[,xy_cols]
+      all_outside <- function(x1, x2) {
+        min(x1) > max(x2) || max(x1) < min(x2)
+      }
+      if (all_outside(xy_orig[,1], xy_nd[,1]) || all_outside(xy_orig[,2], xy_nd[,2])) {
+        cli_warn(c("`newdata` prediction coordinates appear to be ouside the fitted coordinates.",
+          "This will likely cause all your random field values to be returned as 0.",
+          "Check your coordinates including any conversions between projections.",
+          "If working with UTMs, are both in km or m?"))
+      }
+    }
+
     if (object$time == "_sdmTMB_time") newdata[[object$time]] <- 0L
     if (visreg_df) {
       if (!object$time %in% names(newdata)) {

tests/testthat/test-2-fit-less-basic.R

@@ -507,4 +507,29 @@ test_that("Time with an NA gets flagged", {
   }, regexp = "time")
 })
 
+test_that("Prediction outside fitted coordinates gets warned about #285", {
+  fit <- sdmTMB(
+    present ~ 1,
+    family = binomial(),
+    data = pcod_2011,
+    mesh = pcod_mesh_2011
+  )
+  nd <- qcs_grid
+  range(nd$X)
+  nd$X <- nd$X * 10
+  range(nd$X)
+  expect_warning(p <- predict(fit, newdata = nd), regexp = "coordinates")
+
+  nd <- qcs_grid
+  nd$X <- nd$X / 10
+  expect_warning(p <- predict(fit, newdata = nd), regexp = "coordinates")
+
+  nd <- qcs_grid
+  nd$Y <- nd$Y / 10
+  expect_warning(p <- predict(fit, newdata = nd), regexp = "coordinates")
+
+  nd <- qcs_grid
+  nd$Y <- nd$Y * 10
+  expect_warning(p <- predict(fit, newdata = nd), regexp = "coordinates")
+})
 

tests/testthat/test-cross-validation.R

@@ -48,6 +48,7 @@ test_that("Basic cross validation works", {
 })
 
 test_that("Cross validation in parallel with globals", {
+  skip_on_cran()
   # https://github.com/pbs-assess/sdmTMB/issues/127
   d <- pcod
   spde <- make_mesh(d, c("X", "Y"), cutoff = 15)