From 08ac542d0d218d58d568407d338867cc81cfebe3 Mon Sep 17 00:00:00 2001
From: ian fogelman <ian.fogelman@mongodb.com>
Date: Tue, 13 Jul 2021 16:08:48 -0400
Subject: [PATCH] DOCSP-13855-mod-has-inconsistent-rounding

---
 source/reference/operator/query/mod.txt | 58 +++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/source/reference/operator/query/mod.txt b/source/reference/operator/query/mod.txt
index 85ece0f04c7..bd801e4c903 100644
--- a/source/reference/operator/query/mod.txt
+++ b/source/reference/operator/query/mod.txt
@@ -117,3 +117,61 @@ operator with an array that contains four elements:
    	"$err" : "bad query: BadValue malformed mod, too many elements",
    	"code" : 16810
    }
+
+Floating Point Arguments
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``$mod`` expression rounds decimal input towards zero.
+
+The following examples demonstrate this behavior:
+
+.. example::
+
+   Input query:
+
+   .. code-block:: javascript
+
+      db.inventory.find( { qty: { $mod: [ 4.0, 0 ] } } )
+
+   Results:
+
+   .. code-block:: javascript
+      :copyable: false
+
+      { _id: 1, item: 'abc123', qty: 0 }
+      { _id: 3, item: 'ijk123', qty: 12 }
+
+.. example::
+
+   Input query:
+
+   .. code-block:: javascript
+
+      db.inventory.find( { qty: { $mod: [ 4.5, 0 ] } } )
+
+   Results:
+
+   .. code-block:: javascript
+      :copyable: false
+
+      { _id: 1, item: 'abc123', qty: 0 }
+      { _id: 3, item: 'ijk123', qty: 12 }
+
+.. example:: 
+
+   Input query:
+
+   .. code-block:: javascript
+
+      db.inventory.find( { qty: { $mod: [ 4.99, 0 ] } } )
+
+   Results:
+
+   .. code-block:: javascript
+      :copyable: false
+
+      { _id: 1, item: 'abc123', qty: 0 }
+      { _id: 3, item: 'ijk123', qty: 12 }
+
+Each query applies ``4`` to the ``$mod`` expression regardless of 
+decimal points, resulting in the same result set.