From 5773275cb0ad53acf5996e450fd8e0626fbdbbe0 Mon Sep 17 00:00:00 2001
From: twsearle <14909402+twsearle@users.noreply.github.com>
Date: Fri, 7 Feb 2020 18:24:59 +0000
Subject: [PATCH 1/2] Add _natargmax function

Calculate arg max when an array contains `NaT`. Blocker for upgrading to
numpy 1.18.
---
 forest/satellite.py | 13 +++++++++++--
 requirements.txt    |  1 -
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/forest/satellite.py b/forest/satellite.py
index 7a136322a..3626aebaf 100644
--- a/forest/satellite.py
+++ b/forest/satellite.py
@@ -12,6 +12,15 @@
 from forest.exceptions import FileNotFound, IndexNotFound
 
 
+MIN_DATETIME64 = np.datetime64('0001-01-01T00:00:00.000000')
+
+
+def _natargmax(arr):
+    """ Find the arg max when an array contains NaT's"""
+    no_nats = np.where(np.isnat(arr), MIN_DATETIME64, arr)
+    return np.argmax(no_nats)
+
+
 class EIDA50(object):
     def __init__(self, pattern):
         self.locator = Locator(pattern)
@@ -86,7 +95,7 @@ def find_file_index(self, paths, user_date):
             raise FileNotFound(msg)
         before_dates = np.ma.array(
                 dates, mask=mask, dtype='datetime64[s]')
-        return np.ma.argmax(before_dates)
+        return _natargmax(before_dates.filled())
 
     @staticmethod
     def find_index(times, time, length):
@@ -99,7 +108,7 @@ def find_index(times, time, length):
         if valid_times.mask.all():
             msg = "{}: not found".format(time)
             raise IndexNotFound(msg)
-        return np.ma.argmax(valid_times)
+        return _natargmax(valid_times.filled())
 
     @staticmethod
     def parse_date(path):
diff --git a/requirements.txt b/requirements.txt
index 52f9c8f84..7ec27b7f1 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,5 +4,4 @@ intake
 intake-esm
 pygrib
 libwebp=1.0.2  # Pin to prevent Travis issue
-numpy=1.17.*
 xarray

From 9a283adf1afc771045dd6fc1c643f7cd89e6a698 Mon Sep 17 00:00:00 2001
From: twsearle <14909402+twsearle@users.noreply.github.com>
Date: Fri, 7 Feb 2020 18:29:30 +0000
Subject: [PATCH 2/2] Increment version number for fix

---
 forest/__init__.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/forest/__init__.py b/forest/__init__.py
index f7e89c327..898797746 100644
--- a/forest/__init__.py
+++ b/forest/__init__.py
@@ -25,7 +25,7 @@
 .. automodule:: forest.presets
 
 """
-__version__ = '0.7.1'
+__version__ = '0.7.2'
 
 from .config import *
 from . import (