How to Solve Python Xlwt ValueError: More than 4094 XFs (styles)

Solution

For style setting functions:

def define_style():
    font = xlwt.Font()
    font.colour_index = 1
    my_style = xlwt.XFStyle()
    my_style.font = font  
    return my_style

When writing data, do not use sheet.write (0, 0, 'data', define)_ Style ()) in this way, change to:

mystyle = define_style()
sheet.write(0, 0, 'data', mystyle)

Example analysis

The following code will report an error

import xlwt


def define_style():
    font = xlwt.Font()
    font.colour_index = 1
    my_style = xlwt.XFStyle()
    my_style.font = font 
    return my_style


if __name__ == '__main__':
    book = xlwt.Workbook(encoding='utf-8')
    sheet = book.add_sheet('sheet1', cell_overwrite_ok=True)
    # mystyle = define_style()
    for i in range(10000):
        sheet.write(i, 0, u'(0,0)', define_style())  
    book.save('my_excel.xlsx')

Modify the part in main function as follows:

	mystyle = define_style()
	for i in range(10000):
        sheet.write(i, 0, u'(0,0)', mystyle)  

Reason analysis

When using xlwt to write data, when passing in the style of xfstyle format, do not use anonymous function to call to write, otherwise after writing 4094 data, it will exceed the threshold, and an error will be reported: valueerror: more than 4094 XFS (styles)


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