diff --git a/doc/rxsci/latest/_static/documentation_options.js b/doc/rxsci/latest/_static/documentation_options.js
index 2fcd95a..42ac475 100644
--- a/doc/rxsci/latest/_static/documentation_options.js
+++ b/doc/rxsci/latest/_static/documentation_options.js
@@ -1,5 +1,5 @@
 const DOCUMENTATION_OPTIONS = {
-    VERSION: '0.20.0',
+    VERSION: '0.21.0',
     LANGUAGE: 'en',
     COLLAPSE_INDEX: false,
     BUILDER: 'html',
diff --git a/doc/rxsci/latest/genindex.html b/doc/rxsci/latest/genindex.html
index 7dfe9cb..8a74ccf 100644
--- a/doc/rxsci/latest/genindex.html
+++ b/doc/rxsci/latest/genindex.html
@@ -3,7 +3,7 @@
 <head>
   <meta charset="utf-8" />
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Index &mdash; rxsci 0.20.0 documentation</title>
+  <title>Index &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
   <!--[if lt IE 9]>
@@ -12,7 +12,7 @@
   
         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
     <script src="_static/js/theme.js"></script>
diff --git a/doc/rxsci/latest/get_started.html b/doc/rxsci/latest/get_started.html
index 5d2b8af..8fca4f8 100644
--- a/doc/rxsci/latest/get_started.html
+++ b/doc/rxsci/latest/get_started.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Get Started &mdash; rxsci 0.20.0 documentation</title>
+  <title>Get Started &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
     <script src="_static/js/theme.js"></script>
diff --git a/doc/rxsci/latest/index.html b/doc/rxsci/latest/index.html
index f7d26f9..2af222f 100644
--- a/doc/rxsci/latest/index.html
+++ b/doc/rxsci/latest/index.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>RxSci Reference Documentation &mdash; rxsci 0.20.0 documentation</title>
+  <title>RxSci Reference Documentation &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -13,7 +13,7 @@
   
         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/installation.html b/doc/rxsci/latest/installation.html
index 7a46d64..4e45a1f 100644
--- a/doc/rxsci/latest/installation.html
+++ b/doc/rxsci/latest/installation.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Installation &mdash; rxsci 0.20.0 documentation</title>
+  <title>Installation &mdash; rxsci 0.21.0 documentation</title>
       <link rel="stylesheet" href="_static/pygments.css" type="text/css" />
       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
   <!--[if lt IE 9]>
@@ -13,7 +13,7 @@
   
         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
     <script src="_static/js/theme.js"></script>
diff --git a/doc/rxsci/latest/operators.html b/doc/rxsci/latest/operators.html
index 516f7d9..cacf4bd 100644
--- a/doc/rxsci/latest/operators.html
+++ b/doc/rxsci/latest/operators.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Operators &mdash; rxsci 0.20.0 documentation</title>
+  <title>Operators &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -13,7 +13,7 @@
   
         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
     <script src="_static/js/theme.js"></script>
diff --git a/doc/rxsci/latest/operators_compression.html b/doc/rxsci/latest/operators_compression.html
index 4981918..ccb7737 100644
--- a/doc/rxsci/latest/operators_compression.html
+++ b/doc/rxsci/latest/operators_compression.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Compression &mdash; rxsci 0.20.0 documentation</title>
+  <title>Compression &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -13,7 +13,7 @@
   
         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
     <script src="_static/js/theme.js"></script>
diff --git a/doc/rxsci/latest/operators_container.html b/doc/rxsci/latest/operators_container.html
index 43c3f31..7434855 100644
--- a/doc/rxsci/latest/operators_container.html
+++ b/doc/rxsci/latest/operators_container.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Container &mdash; rxsci 0.20.0 documentation</title>
+  <title>Container &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -13,7 +13,7 @@
   
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         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_data.html b/doc/rxsci/latest/operators_data.html
index b78d718..6ceca6f 100644
--- a/doc/rxsci/latest/operators_data.html
+++ b/doc/rxsci/latest/operators_data.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Data &mdash; rxsci 0.20.0 documentation</title>
+  <title>Data &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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@@ -13,7 +13,7 @@
   
         <script src="_static/jquery.js?v=5d32c60e"></script>
         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_error.html b/doc/rxsci/latest/operators_error.html
index 96ccd2c..425aacd 100644
--- a/doc/rxsci/latest/operators_error.html
+++ b/doc/rxsci/latest/operators_error.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Error Operators &mdash; rxsci 0.20.0 documentation</title>
+  <title>Error Operators &mdash; rxsci 0.21.0 documentation</title>
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       <link rel="stylesheet" href="_static/css/theme.css" type="text/css" />
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         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
         <script src="_static/doctools.js?v=888ff710"></script>
         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_framing.html b/doc/rxsci/latest/operators_framing.html
index 840df7c..9191558 100644
--- a/doc/rxsci/latest/operators_framing.html
+++ b/doc/rxsci/latest/operators_framing.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Framing &mdash; rxsci 0.20.0 documentation</title>
+  <title>Framing &mdash; rxsci 0.21.0 documentation</title>
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         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_io.html b/doc/rxsci/latest/operators_io.html
index f040892..795a503 100644
--- a/doc/rxsci/latest/operators_io.html
+++ b/doc/rxsci/latest/operators_io.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>IO &mdash; rxsci 0.20.0 documentation</title>
+  <title>IO &mdash; rxsci 0.21.0 documentation</title>
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-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_math.html b/doc/rxsci/latest/operators_math.html
index 94754a9..f536b81 100644
--- a/doc/rxsci/latest/operators_math.html
+++ b/doc/rxsci/latest/operators_math.html
@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Math &mdash; rxsci 0.20.0 documentation</title>
+  <title>Math &mdash; rxsci 0.21.0 documentation</title>
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         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_other.html b/doc/rxsci/latest/operators_other.html
index 3dbccb2..94d248a 100644
--- a/doc/rxsci/latest/operators_other.html
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@@ -4,7 +4,7 @@
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Base Operators &mdash; rxsci 0.20.0 documentation</title>
+  <title>Base Operators &mdash; rxsci 0.21.0 documentation</title>
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         <script src="_static/_sphinx_javascript_frameworks_compat.js?v=2cd50e6c"></script>
-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/operators_state.html b/doc/rxsci/latest/operators_state.html
index c23004a..0727e72 100644
--- a/doc/rxsci/latest/operators_state.html
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   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>State &mdash; rxsci 0.20.0 documentation</title>
+  <title>State &mdash; rxsci 0.21.0 documentation</title>
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-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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         <script src="_static/sphinx_highlight.js?v=dc90522c"></script>
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diff --git a/doc/rxsci/latest/py-modindex.html b/doc/rxsci/latest/py-modindex.html
index 356d5cc..ff853a3 100644
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@@ -3,7 +3,7 @@
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   <meta charset="utf-8" />
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Python Module Index &mdash; rxsci 0.20.0 documentation</title>
+  <title>Python Module Index &mdash; rxsci 0.21.0 documentation</title>
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-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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diff --git a/doc/rxsci/latest/search.html b/doc/rxsci/latest/search.html
index 521539d..a1d70a5 100644
--- a/doc/rxsci/latest/search.html
+++ b/doc/rxsci/latest/search.html
@@ -3,7 +3,7 @@
 <head>
   <meta charset="utf-8" />
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-  <title>Search &mdash; rxsci 0.20.0 documentation</title>
+  <title>Search &mdash; rxsci 0.21.0 documentation</title>
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-        <script src="_static/documentation_options.js?v=b52c616d"></script>
+        <script src="_static/documentation_options.js?v=c4f92b34"></script>
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