Add floor_divide and remainder (#56)

Author: kgryte

spec/API_specification/elementwise_functions.md

@@ -371,10 +371,6 @@ Calculates the division for each element `x1_i` of the input array `x1` with the
 
     -   divisor input array. Must be compatible with `x1` (see :ref:`broadcasting`).
 
--   **out**:  _Optional\[ <array> ]_
-
-    -   output array. If provided, the output array must be compatible with the provided input arrays (see :ref:`broadcasting`). If not provided or is `None`, an uninitialized return array must be created and then filled with the result of each element-wise computation. Default: `None`.
-
 #### Returns
 
 -   **out**: _<array>_
@@ -473,6 +469,26 @@ Rounds each element `x_i` of the input array `x` to the greatest (i.e., closest
 
     -   an array containing the rounded result for each element in `x`.
 
+### <a name="floor_divide" href="#floor_divide">#</a> floor_divide(x1, x2, /)
+
+Rounds the result of dividing each element `x1_i` of the input array `x1` by the respective element `x2_i` of the input array `x2` to the greatest (i.e., closest to `+infinity`) integer-value number that is not greater than the division result.
+
+#### Parameters
+
+-   **x1**: _&lt;array&gt;_
+
+    -   dividend input array.
+
+-   **x2**: _&lt;array&gt;_
+
+    -   divisor input array. Must be compatible with `x1` (see :ref:`broadcasting`).
+
+#### Returns
+
+-   **out**: _&lt;array&gt;_
+
+    -   an array containing the element-wise results.
+
 ### <a name="greater" href="#greater">#</a> greater(x1, x2, /)
 
 Computes the truth value of `x1_i > x2_i` for each element `x1_i` of the input array `x1` with the respective element `x2_i` of the input array `x2`.
@@ -881,6 +897,26 @@ Calculates an implementation-dependent approximation of exponentiation by raisin
 
     -   an array containing the element-wise results.
 
+### <a name="remainder" href="#remainder">#</a> remainder(x1, x2, /)
+
+Returns the remainder of division for each element `x1_i` of the input array `x1` and the respective element `x2_i` of the input array `x2`.
+
+#### Parameters
+
+-   **x1**: _&lt;array&gt;_
+
+    -   dividend input array.
+
+-   **x2**: _&lt;array&gt;_
+
+    -   divisor input array. Must be compatible with `x1` (see :ref:`broadcasting`).
+
+#### Returns
+
+-   **out**: _&lt;array&gt;_
+
+    -   an array containing the element-wise results. Each element-wise result must have the same sign as the respective element `x2_i`.
+
 ### <a name="round" href="#round">#</a> round(x, /)
 
 Rounds each element `x_i` of the input array `x` to the nearest integer-valued number.