added experimental duration functions

content/v2.0/reference/flux/stdlib/experimental/_index.md

@@ -18,6 +18,8 @@ The Flux Experimental package includes experimental functions that perform vario
 Experimental functions are subject to change at any time and are not recommended for production use.
 {{% /warn %}}
 
+## Experimental functions
 {{< children type="functions" show="pages" >}}
 
-{{< children >}}
+## Experimental packages
+{{< children show="sections" >}}

content/v2.0/reference/flux/stdlib/experimental/addduration.md

@@ -0,0 +1,57 @@
+---
+title: experimental.addDuration() function
+description: >
+  The `experimental.addDuration()` function adds a duration to a time value and
+  returns the resulting time.
+menu:
+  v2_0_ref:
+    name: experimental.addDuration
+    parent: Experimental
+weight: 201
+related:
+  - /v2.0/reference/flux/stdlib/experimental/subduration/
+---
+
+The `experimental.addDuration()` function adds a duration to a time value and
+returns a the resulting time value.
+
+_**Function type:** Transformation_
+
+{{% warn %}}
+The `experimental.addDuration()` function is currently experimental and is subject to change at any time.
+This specific function will be removed once duration vectors are implemented.
+See [influxdata/flux#413](https://github.com/influxdata/flux/issues/413).
+{{% /warn %}}
+
+```js
+import "experimental"
+
+experimental.addDuration(
+  d: 12h,
+  to: now(),
+)
+```
+
+## Parameters
+
+### d
+The duration to add.
+
+_**Data type: Duration**_
+
+### to
+The time to add the [duration](#d) to.
+
+## Examples
+
+### Add six hours to a timestamp
+```js
+import "experimental"
+
+experimental.addDuration(
+  d: 6h,
+  to: 2019-09-16T12:00:00Z,
+)
+
+// Returns 2019-09-16T18:00:00.000000000Z
+```

content/v2.0/reference/flux/stdlib/experimental/bigtable/_index.md

@@ -8,7 +8,7 @@ menu:
   v2_0_ref:
     name: Bigtable
     parent: Experimental
-weight: 202
+weight: 201
 v2.0/tags: [functions, bigtable, package, google]
 ---
 

content/v2.0/reference/flux/stdlib/experimental/bigtable/from.md

@@ -6,7 +6,7 @@ menu:
   v2_0_ref:
     name: bigtable.from
     parent: Bigtable
-weight: 202
+weight: 301
 ---
 
 The `bigtable.from()` function retrieves data from a [Google Cloud Bigtable](https://cloud.google.com/bigtable/)

content/v2.0/reference/flux/stdlib/experimental/mqtt/_index.md

@@ -8,7 +8,7 @@ menu:
   v2_0_ref:
     name: MQTT
     parent: Experimental
-weight: 202
+weight: 201
 v2.0/tags: [functions, mqtt, package]
 ---
 

content/v2.0/reference/flux/stdlib/experimental/mqtt/to.md

@@ -6,7 +6,7 @@ menu:
   v2_0_ref:
     name: mqtt.to
     parent: MQTT
-weight: 202
+weight: 301
 ---
 
 The `mqtt.to()` function outputs data to an MQTT broker using MQTT protocol.

content/v2.0/reference/flux/stdlib/experimental/subduration.md

@@ -0,0 +1,57 @@
+---
+title: experimental.subDuration() function
+description: >
+  The `experimental.subDuration()` function subtracts a duration from a time value and
+  returns a the resulting time value.
+menu:
+  v2_0_ref:
+    name: experimental.subDuration
+    parent: Experimental
+weight: 201
+related:
+  - /v2.0/reference/flux/stdlib/experimental/addduration/
+---
+
+The `experimental.subDuration()` function subtracts a duration from a time value and
+returns a the resulting time value.
+
+_**Function type:** Transformation_
+
+{{% warn %}}
+The `experimental.subDuration()` function is currently experimental and is subject to change at any time.
+This specific function will be removed once duration vectors are implemented.
+See [influxdata/flux#413](https://github.com/influxdata/flux/issues/413).
+{{% /warn %}}
+
+```js
+import "experimental"
+
+experimental.subDuration(
+  d: 12h,
+  from: now(),
+)
+```
+
+## Parameters
+
+### d
+The duration to subtract.
+
+_**Data type: Duration**_
+
+### from
+The time to subtract the [duration](#d) from.
+
+## Examples
+
+### Subtract six hours from a timestamp
+```js
+import "experimental"
+
+experimental.subDuration(
+  d: 6h,
+  from: 2019-09-16T12:00:00Z,
+)
+
+// Returns 2019-09-16T06:00:00.000000000Z
+```