From ef3c46b5175fee7688047e7fadfe2b8c1a47cbd1 Mon Sep 17 00:00:00 2001
From: Jeff Whitaker <jswhit@fastmail.fm>
Date: Mon, 29 Apr 2024 12:42:51 -0600
Subject: [PATCH] add test, Changelog entry

---
 Changelog              |  1 +
 src/cftime/_cftime.pyx |  2 +-
 test/test_cftime.py    | 13 +++++++++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/Changelog b/Changelog
index e9a7e854..f2962d6e 100644
--- a/Changelog
+++ b/Changelog
@@ -2,6 +2,7 @@ since version 1.6.3 release
 ===========================
  * build musllinux wheels (issue #307).
  * return empty array if one provided to date2num (issue #315).
+ * handle nan/inf in num2date (issue #328).
 
 version 1.6.3 (release tag v1.6.3rel)
 =====================================
diff --git a/src/cftime/_cftime.pyx b/src/cftime/_cftime.pyx
index 6329a342..a33ad80c 100644
--- a/src/cftime/_cftime.pyx
+++ b/src/cftime/_cftime.pyx
@@ -621,7 +621,7 @@ def num2date(
     times = np.asanyarray(times)  # Allow list as input
     times = upcast_times(times)
     # convert to masked array if any nan or inf values present
-    if not np.isfinite(times).any():
+    if not np.isfinite(times).all():
         times = np.ma.masked_invalid(times)
     scaled_times = scale_times(times, factor)
     scaled_times = cast_to_int(scaled_times,units=unit)
diff --git a/test/test_cftime.py b/test/test_cftime.py
index 8e9daae7..07d7c6e9 100644
--- a/test/test_cftime.py
+++ b/test/test_cftime.py
@@ -930,6 +930,19 @@ def roundtrip(delta,eps,units):
         # date2num should return an empty array if given one (issue #315)
         d = cftime.date2num([], 'seconds since 2000-01-01 12:00:00')
         assert d.size==0
+        # issue #328:  handle nan/inf in num2date.
+        times = np.array([1,2,3,np.nan],dtype=np.float64)
+        expected = np.array([DatetimeGregorian(2000, 1, 2, 0, 0, 0, 0),
+                             DatetimeGregorian(2000, 1, 3, 0, 0, 0, 0),
+                             DatetimeGregorian(2000, 1, 4, 0, 0, 0, 0),
+                             DatetimeGregorian(2000, 1, 5, 0, 0, 0, 0)])
+        mask = [False, False, False, True]
+        expected = np.ma.masked_array(expected, mask=mask)
+        result = cftime.num2date(times, 'days since 2000-01-01', 'standard')
+        np.testing.assert_equal(result, expected)
+        times = np.array([1,2,3,np.inf],dtype=np.float64)
+        result = cftime.num2date(times, 'days since 2000-01-01', 'standard')
+        np.testing.assert_equal(result, expected)
 
 
 class TestDate2index(unittest.TestCase):