     @table.size *= n
 
     data[id] = new Array @table.size
+    data[idHead] = new Array @table.size
     m = 0
     for col, i in @table.columns when @columns[i]
      for d, j in @table.data[col.id]
       data[id][m + j * n] = d
+      data[idHead][m + j * n] = col.name
      m++
 
     columns = []

     if not @columns[i]
      columns.push col

    columns.push
     id: id
     name: id

    @elems.sidebar.innerHTML = ''

    Weya elem: @elems.sidebar, context: this, ->
     @$.elems.btn = @button '.u-full-width.button-primary', 'Convert to rows',
      on: {click: @$.on.apply}
      style: {display: 'none'}
     @button '.u-full-width', on: {click: @$.on.cancel}, 'Cancel'
