In python removing rows from a excel file using xlrd, xlwt, and xlutils

Question

Hello everyone and thank you in advance.

I have a python script where I am opening a template excel file, adding data (while preserving the style) and saving again.

Answer 1

I achieved using Pandas package....

import pandas as pd

#Read from Excel
xl= pd.ExcelFile("test.xls")

#Parsing Excel Sheet to DataFrame
dfs = xl.parse(xl.sheet_names[0])

#Update DataFrame as per requirement
#(Here Removing the row from DataFrame having blank value in "Name" column)

dfs = dfs[dfs['Name'] != '']

#Updating the excel sheet with the updated DataFrame

dfs.to_excel("test.xls",sheet_name='Sheet1',index=False)

Answer 2

For those of us still stuck with xlrd/xlwt/xlutils, here's a filter you could use:

from xlutils.filter import BaseFilter

class RowFilter(BaseFilter):
    rows_to_exclude: "Iterable[int]"
    _next_output_row: int

    def __init__(
            self,
            rows_to_exclude: "Iterable[int]",
    ):
        self.rows_to_exclude = rows_to_exclude
        self._next_output_row = -1

    def _should_include_row(self, rdrowx):
        return rdrowx not in self.rows_to_exclude

    def row(self, rdrowx, wtrowx):
        if self._should_include_row(rdrowx):
            # Proceed with writing out the row to the output file
            self._next_output_row += 1
            self.next.row(
                rdrowx, self._next_output_row,
            )

    # After `row()` has been called, `cell()` is called for each cell of the row
    def cell(self, rdrowx, rdcolx, wtrowx, wtcolx):
        if self._should_include_row(rdrowx):
            self.next.cell(
                rdrowx, rdcolx, self._next_output_row, wtcolx,
            )

Then put it to use with e.g.:

from xlrd import open_workbook
from xlutils.filter import DirectoryWriter, XLRDReader

xlutils.filter.process(
    XLRDReader(open_workbook("input_filename.xls", "output_filename.xls")),
    RowFilter([3, 4, 5]),
    DirectoryWriter("output_dir"),
)

Answer 3

xlwt does not provide a simple interface for doing this, but I've had success with a somewhat similar problem (inserting multiple copies of a row into a copied workbook) by directly changing the worksheet's rows attribute and the row numbers on the row and cell objects.

Given the number of rows you want to delete and the starting number of the first row you want to keep, something like this might work:

rows_to_move = worksheet.rows[first_kept_row:]
for row in rows_to_move:
    new_row_number = row._Row__idx - number_to_delete
    row._Row__idx = new_row_number
    for cell in row._Row__cells.values():
        if cell:
            cell.rowx = new_row_number
    worksheet.rows[new_row_number] = row
# now delete any remaining rows
del worksheet.rows[new_row_number + 1:]

Do you have merged ranges in the rows you want to delete, or below them? If so you'll also need to run through the worksheet's merged_ranges attribute and update the rows for them. Also, if you have more rows to delete than rows in your footer, you'll need to

As a side note - I was able to write text to my worksheet and preserve the predefined style thus:

def write_with_style(ws, row, col, value):
    if ws.rows[row]._Row__cells[col]:
        old_xf_idx = ws.rows[row]._Row__cells[col].xf_idx
        ws.write(row, col, value)
        ws.rows[row]._Row__cells[col].xf_idx = old_xf_idx
    else:
        ws.write(row, col, value)

That might let you skip having two copies of your spreadsheet open at once.