(DOCSP-11753) Document aggregation options (#413)

* (DOCSP-11753) Document aggregation options

Author: zach-carr

config/sphinx_local.yaml

@@ -26,6 +26,7 @@ theme:
      - /chart-type-reference/choropleth
      - /chart-type-reference/grid-charts
      - /chart-type-reference/circular-charts
+     - /encoding-channels
      - /customize-charts
      - /embedding-charts
      - /view-export-chart-data

source/encoding-channels.txt

@@ -58,10 +58,10 @@ data). The following table describes each encoding channel type in
 
    * - Aggregation
      - A point on the chart is created by applying an
-       :manual:`aggregation <aggregation>` function over the values of
+       :manual:`aggregation </aggregation>` function over the values of
        this field from multiple documents. For more
-       information on aggregation in |charts-short|, see the
-       :ref:`Aggregation <building-charts-aggregation>` section.
+       information on using aggregation functions in |charts-short|, see 
+       :ref:`Aggregation Options <aggregation-options>`.
 
    * - Geopoint
      - When you create a chart using a geopoint channel type, |charts|
@@ -87,11 +87,10 @@ Aggregation
 Dragging a field onto an :guilabel:`aggregation`
 :ref:`encoding channel <encoding-channels>` allows you to use an
 :manual:`aggregation pipeline operator </reference/operator/aggregation/>`
-on that field. The aggregation operators available in the chart
-builder change based on the :manual:`data type </reference/bson-types/>`
-of the selected field. MongoDB Charts categorizes the field data type
-as either a ``number``, ``string``, or ``date`` and displays
-appropriate aggregation options accordingly.
+on that field. 
+
+For a list of the available aggregation pipeline operators in 
+|charts-short|, see :ref:`Aggregation Options <aggregation-options>`.
 
 .. example::
 
@@ -204,3 +203,10 @@ fields in the same subdocument, |charts| also adds those fields in
 italics. Once you add a field, you can include it in your chart,
 :doc:`convert its data type </convert-field-data-types>`, or
 :ref:`remove it <remove-calculated-field>`. 
+
+.. class:: hidden
+
+   .. toctree::
+      :titlesonly:
+
+      /encoding-channels/aggregation-options

source/encoding-channels/aggregation-options.txt

@@ -0,0 +1,112 @@
+.. _aggregation-options:
+
+===================
+Aggregation Options
+===================
+
+.. default-domain:: mongodb
+
+.. contents:: On this page
+   :local:
+   :backlinks: none
+   :depth: 1
+   :class: singlecol
+
+Dragging a field onto an :guilabel:`aggregation`
+:ref:`encoding channel <encoding-channels>` allows you to use an
+:manual:`aggregation pipeline operator </reference/operator/aggregation/>`
+on that field.
+
+The aggregation pipeline operators available in the chart
+builder change based on the :manual:`data type </reference/bson-types/>`
+of the selected field. MongoDB Charts categorizes the field data type
+as either a ``number``, ``string``, or ``date`` and displays
+appropriate aggregation options accordingly.
+
+The following tables list the available aggregation options for each 
+data type:
+
+Numbers
+-------
+
+.. list-table::
+   :header-rows: 1
+   :stub-columns: 1
+   :widths: 20 40 40
+
+   * - Aggregation Option
+     - Description
+     - Pipeline Operation
+
+   * - ``sum``
+     - Sums all values in the field.
+     - :manual:`$sum </reference/operator/aggregation/sum/>`
+
+   * - ``count``
+     - Counts the number of documents with a value in the field.
+     - :manual:`$count </reference/operator/aggregation/count/>`
+
+   * - ``distinct``
+     - Counts the number of unique values in the field.
+     - Applies
+       :manual:`$addToSet </reference/operator/aggregation/addToSet/>`
+       and counts the number of items in the result set with
+       :manual:`$size </reference/operator/aggregation/size/>`.
+
+   * - ``mean``
+     - Averages all values in the field.
+     - :manual:`$avg </reference/operator/aggregation/avg/>`
+
+   * - ``min``
+     - Returns the minimum value in the field.
+     - :manual:`$min </reference/operator/aggregation/min/>`
+
+   * - ``max``
+     - Returns the minimum value in the field.
+     - :manual:`$max </reference/operator/aggregation/max/>`
+
+   * - ``variance``
+     - Calculates the sample variance of values in the field.
+     - Applies 
+       :manual:`$stdDevSamp </reference/operator/aggregation/stdDevSamp/>` 
+       and raises the result to the 2nd power with 
+       :manual:`$pow </reference/operator/aggregation/pow/>`.
+
+   * - ``variancep``
+     - Calculates the population variance of values in the field.
+     - Applies 
+       :manual:`$stdDevPop </reference/operator/aggregation/stdDevPop/>` 
+       and raises the result to the 2nd power with
+       :manual:`$pow </reference/operator/aggregation/pow/>`.
+
+   * - ``stdev``
+     - Calculates the sample standard deviation of values in the field.
+     - :manual:`$stdDevSamp </reference/operator/aggregation/stdDevSamp/>`
+
+   * - ``stdevp``
+     - Calculates the population standard deviation of values in the 
+       field.
+     - :manual:`$stdDevPop </reference/operator/aggregation/stdDevPop/>`
+
+Strings and Dates
+-----------------
+
+.. list-table::
+   :header-rows: 1
+   :stub-columns: 1
+   :widths: 20 40 40
+
+   * - Aggregation Option
+     - Description
+     - Pipeline Operation
+
+   * - ``count``
+     - Counts the number of documents with a value in the field.
+     - :manual:`$count </reference/operator/aggregation/count/>`
+
+   * - ``distinct``
+     - Counts the number of unique values in the field.
+     - Applies the 
+       :manual:`$addToSet </reference/operator/aggregation/addToSet/>`
+       operator and counts the number of items in the result set with
+       :manual:`$size </reference/operator/aggregation/size/>`.