diff --git a/CHANGELOG.md b/CHANGELOG.md
index e17b5a1..b595eac 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,10 +5,19 @@ All notable changes to this project will be documented in this file
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.4.0][] ~ 2023-01-24
+
+- update to HELICS [3.4.0](https://github.com/GMLC-TDC/HELICS/releases/tag/v3.4.0) release
+- update matlab docstrings on extra matlab codes
+
 ## [3.3.2][] ~ 2022-12-16
 
-- update to HELICS 3.3.2 release
+- update to HELICS [3.3.2](https://github.com/GMLC-TDC/HELICS/releases/tag/v3.3.2) release
 
 ## [3.2.1][] ~ 2022-06-03
 
 Initial version to match [HELICS](www.github.com/GMLC-TDC/HELICS) versioning.
+
+[3.2.1]: https://github.com/GMLC-TDC/matHELICS/releases/tag/v3.2.1
+[3.3.2]: https://github.com/GMLC-TDC/matHELICS/releases/tag/v3.3.2
+[3.4.0]: https://github.com/GMLC-TDC/matHELICS/releases/tag/v3.4.0
\ No newline at end of file
diff --git a/LICENSE b/LICENSE
index 2fae2b7..52a1844 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 BSD 3-Clause License
 
-Copyright (c) 2017-2022, Battelle Memorial Institute; Lawrence Livermore National Security, LLC; Alliance for Sustainable Energy, LLC.
+Copyright (c) 2017-2023, Battelle Memorial Institute; Lawrence Livermore National Security, LLC; Alliance for Sustainable Energy, LLC.
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
diff --git a/extra_m_codes/helicsInputSetDefault.m b/extra_m_codes/helicsInputSetDefault.m
index 9bd5e7a..b4ff858 100644
--- a/extra_m_codes/helicsInputSetDefault.m
+++ b/extra_m_codes/helicsInputSetDefault.m
@@ -1,4 +1,9 @@
 function  helicsInputSetDefault(varargin)
+%set the default value for a HELICS input
+%helicsInputSetDefault(inp,value)
+%inp is the input object
+% value is the data value to set as the default can be a char,integer, double, vector, logical, or string. 
+
     pubdata=varargin{2};
     import helics.*
    switch (class(pubdata))
diff --git a/extra_m_codes/helicsPublicationPublish.m b/extra_m_codes/helicsPublicationPublish.m
index a8ff470..dc2778c 100644
--- a/extra_m_codes/helicsPublicationPublish.m
+++ b/extra_m_codes/helicsPublicationPublish.m
@@ -1,4 +1,8 @@
 function  helicsPublicationPublish(varargin)
+%publish a value through HELICS
+%helicsPublicationPublish(pub,value)
+%pub is the publication object
+% value is the data value to set as the default can be a char,integer, double, vector, logical, or string. 
     pubdata=varargin{2};
     import helics.*
    switch (class(pubdata))