8excel_column_by_name.py

#!/usr/bin/env python3
import sys
from datetime import date
from xlrd import open_workbook, xldate_as_tuple
from xlwt import Workbook

input_file = sys.argv[1]
output_file = sys.argv[2]

output_workbook = Workbook()
output_worksheet = output_workbook.add_sheet('jan_2013_output')

my_columns = ['Customer ID', 'Purchase Date']

with open_workbook(input_file) as workbook:
	worksheet = workbook.sheet_by_name('january_2013')
	data = [my_columns]
	header_list = worksheet.row_values(0)
	header_index_list = []
	for header_index in range(len(header_list)):
		if header_list[header_index] in my_columns:
			header_index_list.append(header_index)
	for row_index in range(1,worksheet.nrows):
		row_list = []
		for column_index in header_index_list:
			cell_value = worksheet.cell_value(row_index,column_index)
			cell_type = worksheet.cell_type(row_index, column_index)
			if cell_type == 3:
				date_cell = xldate_as_tuple(cell_value,workbook.datemode)
				date_cell = date(*date_cell[0:3]).strftime('%m/%d/%Y')
				row_list.append(date_cell)
			else:
				row_list.append(cell_value)
		data.append(row_list)

	for list_index, output_list in enumerate(data):
		for element_index, element in enumerate(output_list):
			output_worksheet.write(list_index, element_index, element)

output_workbook.save(output_file)