Similarly, if you assign a dimension name that is not a valid MATLAB identifier, the name
is modified.
T.Properties.DimensionNames{1} = 'Last Name';
T.Properties.DimensionNames
Warning: DimensionNames property was modified to make the name 'Last Name' a valid MATLAB
identifier. See Compatibility Considerations for Using Tables for more details. This will
become an error in a future release.
ans =
1×2 cell array
'LastName' 'Data'
In R2016b, tables raise warnings when dimension names are not valid identifiers, or
conflict with variable names or reserved names, so that you can continue to work with
code and tables created with previous releases. If you encounter these warnings, it is
recommended that you update your code to avoid them.
Changes to DimensionNames Property in R2016b