xlrd named range example? - python-3.x

Question

I have an excel spreadsheet that I am trying to parse with xlrd. The spreadsheet itself makes extensive use of named ranges.
If I use:
for name in book.name_map:
print(name)
I can see all of the names are there.
However I can't make any of the methods work (cell method and area2d). Can anyone give me an example of the syntax to be able to read the cell range that a name is pointing to given the name.
The Excel file is an XLSM file with lots of visual basic that also operates on these named ranges.

Answer 1

I think that the naming support in XLRD is broken for XLSM files but I found an answer by switching to openpyxl. This has a function get_named_ranges() which contains all of the named ranges. The support after that is a bit thin so I wrote my own class to turn the named ranges in my spreadsheet into a class where I can access the same information using the same names.
# -- coding: utf-8 --
"""
Created on Wed Sep 14 09:42:09 2016
#author: ellwood
"""
from openpyxl import load_workbook
class NamedArray(object):
''' Named range object
'''
C_CAPS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
def __init__(self, workbook, named_range_raw):
''' Initialise a NameArray object from the named_range_raw information in the given
workbook
'''
self.wb = workbook
sheet_str, cellrange_str = str(named_range_raw).split('!')
self.sheet =sheet_str.split('"')[1]
self.loc = self.wb[self.sheet]
if ':' in cellrange_str:
self.has_range = True
self.has_value = False
lo,hi = cellrange_str.split(':')
self.ad_lo = lo.replace('$','')
self.ad_hi = hi.replace('$','')
else:
self.has_range = False
self.has_value = True
self.ad_lo = cellrange_str.replace('$','')
self.ad_hi = self.ad_lo
self.min_row = self.get_row(self.ad_lo)
self.max_row = self.get_row(self.ad_hi)
self.rows = self.max_row - self.min_row + 1
self.min_col = self.col_to_n(self.ad_lo)
self.max_col = self.col_to_n(self.ad_hi)
self.cols = self.max_col - self.min_col + 1
def size_of(self):
''' Returns two dimensional size of named space
'''
return self.cols, self.rows
def cols(self):
''' Returns number of cols in named space
'''
return self.cols
def rows(self):
''' Returns number of rows in named space
'''
return self.rows
def value(self, r=1, c=1):
''' Returns the value at row r, column c
'''
if self.has_value:
return self.loc.cell(self.ad_lo).value
assert r < self.max_rows
assert c < self.max_cols
return self.loc.cell(self.n_to_col(self.min_col + c-1)+str(self.min_row+r-1)).value
def is_range(self):
''' if true then name defines a table more than 1 cell
'''
return self.range
def is_value(self):
''' if true then name defines the location of a single value
'''
return None
def __str__(self):
''' printed description of named space
'''
locs = 's ' + self.ad_lo + ':' + self.ad_hi if self.is_range else ' ' + self.ad_lo
return('named range'+ str(self.size_of()) + ' in sheet ' + self.sheet + ' # location' + locs)
#classmethod
def get_row(cls, ad):
''' get row number from cell string
Cell string is assumed to be in excel format i.e "ABC123" where row is 123
'''
row = 0
for l in ad:
if l in "1234567890":
row = row*10 + int(l)
return row
#classmethod
def col_to_n(cls, ad):
''' find column number from xl address
Cell string is assumed to be in excel format i.e "ABC123" where column is abc
column number is integer represenation i.e.(A-A)*26*26 + (B-A)*26 + (C-A)
'''
n = 0
for l in ad:
if l in cls.C_CAPS:
n = n*26 + cls.C_CAPS.find(l)+1
return n
#classmethod
def n_to_col(cls,n):
''' make xl column address from column number
'''
ad = ''
while n > 0:
ad = cls.C_CAPS[n%26-1] + ad
n = n // 26
return ad
class Struct(object):
''' clast which turns a dictionary into a structure
'''
def __init__(self, **entries):
self.__dict__.update(entries)
def repr__(self):
return '<%s>' % str('\n '.join('%s : %s' % (k, repr(v)) for (k, v) in self.__dict.iteritems()))
def get_names(workbook):
''' Get a structure containing all of the names in the workbook
'''
named_ranges = wb.get_named_ranges()
name_list = {}
for named_range in named_ranges:
name = named_range.name
if name[0:2] == 'n_':
# only store the names beginning with 'n_'
name_list[name[2:]] = NamedArray(wb, str(named_range))
for item in name_list:
print (item, '=', name_list[item])
return Struct(**name_list)
# ------------------
# program example
# -----------------
wb = load_workbook('test.xlsm', data_only=True)
n = get_names(wb)
print(n.my_name.value())
One Small optimisation is that I prefixed all of the names I was interested in importing wiht 'n_' so I could then ignore any built in Excel names. I hope this is useful to someone.