From 234fcb15ed1de846a39c59930598cdf0cad978b6 Mon Sep 17 00:00:00 2001
From: Joe Roe <git@joeroe.io>
Date: Thu, 17 Oct 2024 15:11:08 +0200
Subject: [PATCH] Normalise value of cal_interpolate()

---
 R/cal.R                   | 8 +++++++-
 R/cal_aggregate.R         | 2 +-
 tests/testthat/test-cal.R | 4 ++++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/R/cal.R b/R/cal.R
index e2f04df..5f85fb4 100644
--- a/R/cal.R
+++ b/R/cal.R
@@ -177,8 +177,14 @@ cal_age_common <- function(x, resolution = 1) {
 
 #' Interpolate a cal vector over the given range
 #'
+#' Result is normalised
+#'
 #' @noRd
 #' @keywords internal
 cal_interpolate <- function(x, range = cal_age_common(x)) {
-  new_cal(furrr::future_map(vec_data(x), \(x) approx_df(x, range, ties = "ordered")))
+  new_cal(furrr::future_map(vec_data(x), function(x) {
+    x <- approx_df(x, range, ties = "ordered")
+    x$pdens <- x$pdens / sum(x$pdens, na.rm = TRUE)
+    x
+  }))
 }
\ No newline at end of file
diff --git a/R/cal_aggregate.R b/R/cal_aggregate.R
index 78fc305..5449c9f 100644
--- a/R/cal_aggregate.R
+++ b/R/cal_aggregate.R
@@ -32,7 +32,7 @@ cal_sum <- function(x, range = cal_age_common(x), normalise = FALSE, ...) {
   x <- cal_interpolate(x, range)
 
   pdens_sum <- furrr::future_pmap_dbl(cal_pdens(x), \(...) sum(..., na.rm = TRUE))
-  if (isTRUE(normalise)) pdens_sum <- pdens_sum / sum(pdens_sum)
+  if (isTRUE(normalise)) pdens_sum <- pdens_sum / sum(pdens_sum, na.rm = TRUE)
 
   new_cal(list(data.frame(age = cal_age(x)[[1]], pdens = pdens_sum)))
 }
\ No newline at end of file
diff --git a/tests/testthat/test-cal.R b/tests/testthat/test-cal.R
index 38b1d9c..ab6d1e9 100644
--- a/tests/testthat/test-cal.R
+++ b/tests/testthat/test-cal.R
@@ -16,3 +16,7 @@ test_that("cal_age_common() returns a yr vector", {
   # TODO: somehow test the expected length?
   expect_vector(cal_age_common(y), y_yr_ptype)
 })
+
+test_that("cal_interpolate() is normalised", {
+  expect_equal(sum(cal_pdens(cal_interpolate(x))[[1]]), 1)
+})