Optimizing XLStoCSV Code in Python

[fsgpr]

I am a relative Python/Programming noob...

Below is some code I wrote to convert XLS files to CSV. While it works, it is rather slow on larger files.

Please let me know what the best ways to optimize this code are. I know that I should combine strings using join, but am not quite sure how to implement it in this case... Should I join on '","', use slices to eliminate the extra characters at the beginning and end of a line, and add a '\n'? (it just seems there should be a better way)

I am using the xlrd package from http://www.lexicon.net/sjmachin/xlrd.htm.

Any advice is appreciated, thanks.



def XLSToCSV(XLSFileName, CSVFileName):
book = xlrd.open_workbook(XLSFileName)
sheet = book.sheet_by_index(0)
CSVFileString = ""
for row in range(sheet.nrows):
for column in range(sheet.ncols):
if(sheet.cell_type(row, column) == xlrd.XL_CELL_DATE):
Date = sheet.cell_value(row, column)
Date = xlrd.xldate_as_tuple(Date, book.datemode)
DateString = LeadingZero(Date[1]) + "/" + LeadingZero(Date[2]) + "/" + str(Date[0])
CSVFileString = CSVFileString + '"' + DateString + '",'
elif(sheet.cell_type(row, column) == xlrd.XL_CELL_NUMBER):
Number = sheet.cell_value(row, column)
Number = str(Number)
if(Number[-2:] == ".0"):
Number = Number[:-2]
CSVFileString = CSVFileString + '"' + Number + '",'
else:
CSVFileString = CSVFileString + '"' + str(sheet.cell_value(row, column)) + '",'
CSVFileString = CSVFileString + "\n"
CSVFile = open(CSVFileName, 'w')
CSVFile.write(CSVFileString)
CSVFile.close()

def LeadingZero(Date):
Date = str(Date)
if(len(Date) == 1):
Date = "0" + str(Date)
return str(Date)