Openpyxl setting number format

Question

Could please someone show an example of applying the number format to the cell. For example, I need scientific format, form would be like '2.45E+05' but I couldn't figure a way how to do that in openpyxl.

I tried in several ways but they are all reporting errors when saving the workbook.

for example:

    import openpyxl as oxl

    wb = oxl.Workbook()
    ws = wb.create_sheet(title='testSheet')
    _cell = ws.cell('A1')
    _cell.style.number_format = '0.00E+00'

or this (here I'm trying to use some of the predefined number formats, I have also seen there is engineering format in builtins but don't know how to access it:

    nf = oxl.style.NumberFormat.FORMAT_NUMBER_00
    _cell.style.number_format = nf

In both cases I get the same error:

C:\Python27\openpyxl\cell.pyc in is_date(self)
    408         """
    409         return (self.has_style
--> 410                 and self.style.number_format.is_date_format()
    411                 and isinstance(self._value, NUMERIC_TYPES))

AttributeError: 'str' object has no attribute 'is_date_format'

I have seen this question: Setting styles in Openpyxl but it doesn't help because I don't have to change any other formatting settings.

Answer 1

This answer works with openpyxl 2.0. (The previously accepted answer does not.)

The number_format can be changed directly.

The given example becomes:

from openpyxl import Workbook

wb = Workbook()
ws = wb.create_sheet(title='testSheet')
_cell = ws.cell('A1')
_cell.number_format = '0.00E+00'

Answer 2

Note: this answer worked with earlier versions of openpyxl, but does not work with openpyxl 2.0

This is how to do it:

    _cell.style.number_format.format_code = '0.00E+00' 

Answer 3

For openpyxl version 2.6.2: note the float display depends on the magnitude when in a python shell, or idle, or ipython session,

>>> wb = load_workbook('tmp.xlsx')
>>> ws = wb[wb.sheetnames[0]]
>>> c21 = ws.cell(2,1)
>>> c21.value
'43546'
>>> c21.value = int(c21.value)
>>> c21.value
43546
>>> c21.value = 134352345235253235.235235
>>> c21.number_format = '0.000E+00'
>>> c21.value
1.3435234523525323e+17
>>> c21.value = 534164134.6643
>>> c21.value
534164134.6643
>>> wb.save('tmp_a.xlsx')
>>> wb.close()

But do not be dismayed, because the '0.000E+00' format will be displayed correctly when you re-open the spreadsheet with MS-Excel or LibreOffice-Calc or Gnumeric. Just remember to save the workbook.