title: Column and row dimensions in OpenPyXL are always None
body: <p>Why is openpyxl reading every row and column dimension as None? This is the case regardless of whether the table was created via openpyxl or within Microsoft Excel.</p>
  
  <pre><code>import openpyxl
  wb = openpyxl.load_workbook(r'C:\data\MyTable.xlsx')
  ws = wb.active
  print ws.row_dimensions[1].height
  print ws.column_dimensions['A'].width
  </code></pre>
  
  <p>prints None and None. These aren't hidden columns/rows. They clearly have dimensions when viewed in Excel.</p>
  
  <p>I know that loading the workbook with iterators will prevent the dimension dictionaries from being created, but that results in key errors, and I'm not using iterators here.</p>
  
  <p>Is there an alternative way to determine the width/height of a cell/row/column?</p>
  
  <p>===============SOLUTION=================</p>
  
  <p>Thanks to Charlie, I realized that the following is the best way to get a list of all row heights:</p>
  
  <pre><code>import openpyxl
  wb = openpyxl.load_workbook(r'C:\Data\Test.xlsx')
  ws = wb.active
  rowHeights = [ws.row_dimensions[i+1].height for i in range(ws.max_row)]
  rowHeights = [15 if rh is None else rh for rh in rowHeights]
  </code></pre>