Python Programming/Excel
Python has multiple 3rd party libraries for reading and writing Microsoft Excel spreadsheet files, including .xls and .xlsx.
For working with .xls files, there is xlrd for reading and xlwt for writing.
For working with .xlsx files, there is xlrd for reading, openpyxl for reading and writing, and XlsxWriter and PyExcelerate for writing.
To interact with the Excel application and create Python-based add-ins: xlwings, xlOil, PyXLL (commercial).
xlrd
[edit | edit source]Supports reading .xls Excel files. Support for .xlsx files was removed in xlrd version 2.0.0 from Dec 2020 due to security concerns, but is still available in xlrd version 1.2.0 from Dec 2018. License: BSD.
Example:
import xlrd
workbook = xlrd.open_workbook("MySpreadsheet.xls")
#for sheet in workbook.sheets(): # Loads all the sheets, unlike workbook.sheet_names()
for sheetName in workbook.sheet_names(): # Sheet iteration by name
print("Sheet name:", sheetName)
sheet = workbook.sheet_by_name(sheetName)
for rowno in range(sheet.nrows):
for colno in range(sheet.ncols):
cell = sheet.cell(rowno, colno)
print(str(cell.value)) # Output as a string
if cell.ctype == xlrd.XL_CELL_DATE:
dateTuple = xlrd.xldate_as_tuple(cell.value, workbook.datemode)
print(dateTuple) # E.g. (2017, 1, 1, 0, 0, 0)
mydate = xlrd.xldate.xldate_as_datetime(cell.value, workbook.datemode)
print(mydate) # In xlrd 0.9.3
print()
for sheetno in range(workbook.nsheets): # Sheet iteration by index
sheet = workbook.sheet_by_index(sheetno)
print("Sheet name:", sheet.name)
for notekey in sheet.cell_note_map: # In xlrd 0.7.2
print("Note AKA comment text:", sheet.cell_note_map[notekey].text)
print(xlrd.formula.colname(1)) # Column name such as A or AD, here 'B'
Links:
- xlrd, pypi.python.org
- xlrd 1.2.0, pypi.python.org
- xlrd documentation, readthedocs.io
- xlrd API documentation, readthedocs.io
- Python: xlrd discerning dates from floats, stackoverflow.com
- xlrd.biffh.XLRDError: Excel xlsx file; not supported, 11 Dec 2020, stackoverflow.com
- xlrd 2 released, 11 Dec 2020, groups.google.com
xlwt
[edit | edit source]Supports writing .xls files. License: BSD.
Links:
- xlwt, pypi.python.org
- xlwt documentation, readthedocs.io
openpyxl
[edit | edit source]Supports reading and writing .xlsx Excel files. Does not support .xls files. License: MIT.
Reading a workbook:
from openpyxl import load_workbook
workbook = load_workbook("MyNewWorkbook.xlsx")
for worksheet in workbook.worksheets:
print("==%s==" % worksheet.title)
for row in worksheet: # For each cell in each row
for cell in row:
print(cell.row, cell.column, cell.value) # E.g. 1 A Value
for cell in worksheet["A"]: # For each cell in column A
print(cell.value)
print(worksheet["A1"].value) # A single cell
print(worksheet.cell(column=1, row=1).value) # A1 value as well
Creating a new workbook:
from openpyxl import Workbook
workbook = Workbook()
worksheet = workbook.worksheets[0]
worksheet['A1'] = 'String value'
worksheet['A2'] = 42 # Numerical value
worksheet.cell(row=3, column=1).value = "New A3 Value"
workbook.save("MyNewWorkbook.xlsx") # Overrides if it exists
Changing an existing workbook:
from openpyxl import load_workbook
workbook_name = 'MyWorkbook.xlsx'
workbook = load_workbook(workbook_name)
worksheet = workbook.worksheets[0]
worksheet['A1'] = "String value"
workbook.save(workbook_name)
Links:
- openpyxl, pypi.org
- openpyxl - A Python library to read/write Excel 2010 xlsx/xlsm files, readthedocs.io
XlsxWriter
[edit | edit source]Supports writing of .xlsx files. License: BSD.
Links:
- XlsxWriter, pypi.org
- Creating Excel files with Python and XlsxWriter, readthedocs.io
PyExcelerate
[edit | edit source]Supports writing .xlsx files. License: BSD.
Links:
- PyExcelerate, pypi.org
xlutils
[edit | edit source]Supports various operations and queries on .xls files; depends on xlrd and xlwt. License: MIT.
Links:
- xlutils, pypi.org
xlOil
[edit | edit source]Supports creation of Python-based Excel add-ins. Requires Python 3.6 or later; requires Excel 2010 or later installed. Supports: global and local scope worksheet functions, ribbon customisation, custom task panes, RTD/async functions, numpy, matplotlib, pandas, jupyter. Low overhead function calls due to use of the Excel's C-API and embedded in-process Python
Examples:
Create a function to add one day to a date:
import datetime as dt
@xloil.func
def pyTestDate(x: dt.datetime) -> dt.datetime:
return x + dt.timedelta(days=1)
Create a function which give a live ticking clock in an cell (uses RTD):
@xloil.func
async def pyTestAsyncGen(secs):
while True:
await asyncio.sleep(secs)
yield datetime.datetime.now()
Links:
pywin32
[edit | edit source]Supports access to Windows applications via Windows Component Object Model (COM). Thus, on Windows, if Excel is installed, PyWin32 lets you call it from Python and let it do various things. You can install PyWin32 by downloading a .exe installer from SourceForge, where it is currently hosted.
Links:
- 3.4.1. PyWin32, docs.python.org
- pywin32, pypi.org
- Python for Windows Extensions files, sourceforge.net
- Python Excel Mini Cookbook, pythonexcels.com
External links
[edit | edit source]- Working with Excel Files in Python, python-excel.org -- has links to source code repositories (GitHub, etc.) for the packages