571 Add "from MATLAB Table" example to Dynamic Tables tutorial (#604)

* Fix: Ensure autogenerated id column is column vector in util.table2nwb

* Add table's variable description to vectordata description property

* Add nwb type descriptions to table's VariableDescription property

* Add conversion from table to nwb table in tutorial (Issue #571 )

* Fix failing test

+tests/+system/DynamicTableTest.m

@@ -233,7 +233,10 @@ function toTableTest(testCase)
             ExpectedSubTable = testCase.file.intervals_trials.getRow(1:20);
             % convert DynamicTable to MATLAB table
             TrialsTable = testCase.file.intervals_trials.toTable();
-            TrialsTable.id = []; %remove id column
+            % Remove id column and variable descriptions as they are not
+            % present in the ExpectedSubTable retrieved from getRow method
+            TrialsTable.id = [];
+            TrialsTable.Properties.VariableDescriptions = {};
             % retrieve rows from MATLAB table
             ActualSubTable = TrialsTable(1:20,:);
             % compare

+types/+util/+dynamictable/nwbToTable.m

@@ -51,6 +51,7 @@
 
 % deal with DynamicTableRegion columns when index is false
 [columns, remainingColumns] = deal(DynamicTable.colnames);
+columnDescriptions = repmat({''}, 1, length(columns));
 
 for i = 1:length(columns)
     cn = columns{i};
@@ -61,6 +62,7 @@
     else
         cv = DynamicTable.vectordata.get(cn);
     end
+    columnDescriptions{i} = cv.description;
     if ~index && ...
             (isa(cv,'types.hdmf_common.DynamicTableRegion') ||...
             isa(cv,'types.core.DynamicTableRegion'))
@@ -85,3 +87,6 @@
 
 % Update the columns order to be the same as the original 
 matlabTable = matlabTable(:, [{'id'}, columns]);
+
+% Add variable descriptions
+matlabTable.Properties.VariableDescriptions = [{''}, columnDescriptions];

+util/table2nwb.m

@@ -18,7 +18,7 @@
 if ismember('id', T.Properties.VariableNames)
     id = T.id;
 else
-    id = 0:height(T)-1;
+    id = transpose( 0:height(T)-1 ); % Must be column vector
 end
 
 nwbtable = types.hdmf_common.DynamicTable( ...
@@ -28,8 +28,15 @@
 
 for col = T
     if ~strcmp(col.Properties.VariableNames{1},'id')
+
+        if ~isempty(col.Properties.VariableDescriptions{1})
+            description = col.Properties.VariableDescriptions{1};
+        else
+            description = 'no description provided';
+        end
+
         nwbtable.vectordata.set(col.Properties.VariableNames{1}, ...
             types.hdmf_common.VectorData('data', col.Variables',...
-            'description', 'my description'));
+            'description', description));
     end
 end