set
(Not Recommended) Set and display dataset array properties
The dataset data type is not recommended. To work with heterogeneous data,
        use the MATLAB®
        table data type instead. See MATLAB
        table documentation for more information.
Syntax
set(A)
set(A,PropertyName)
A = set(A,PropertyName,PropertyValue,...)
B = set(A,PropertyName,value)
Description
set(A) displays all properties of the dataset
         array A and their possible values.
set(A,
         displays possible values for the property specified by
            PropertyName)PropertyName.
A = set(A,
         sets property name/value pairs.PropertyName,PropertyValue,...)
B = set(A, returns a
         dataset array PropertyName,value)B that is a copy of A, but with the
         property 'PropertyName' set to the value value. 
Note
Using set(A,'PropertyName',value) without assigning to a variable
            does not modify A's properties. Use A = set(A,'PropertyName',value)
            to modify A. 
Examples
Create a dataset array from Fisher's iris data and add a description:
load fisheriris
NumObs = size(meas,1);
NameObs = strcat({'Obs'},num2str((1:NumObs)','%-d'));
iris = dataset({nominal(species),'species'},...
               {meas,'SL','SW','PL','PW'},...
               'ObsNames',NameObs);
iris = set(iris,'Description','Fisher''s Iris Data');
get(iris)
   Description: 'Fisher's Iris Data'
   Units: {}
   DimNames: {'Observations' 'Variables'}
   UserData: []
   ObsNames: {150x1 cell}
   VarNames: {'species' 'SL' 'SW' 'PL' 'PW'}