使用xlrd读取python中的选定列和所有行

Question

I would like to loop through an excel table and get the values for selected columns in each row in a set of lists or dictionary. if in a dictionary, for each row, the value in the first selected column would be the key and the values in the other selected columns would be the values (array) for that key. I cannot figure out how to tell python to read values from only selected columns...for the excel table may have 10 columns but I am only interest in three for example, and the three of interest are not contiguous. Would appreciate your insights using XLRD.

    import xlrd
    from xlrd import open_workbook
    import arcpy

    wb = open_workbook ("c:\\Users\\Admin\\Documents\\Marion\\Courses\\GEOG485\\FinalProject\\Data\\ExcelFiles\\Belize_Culvert_Nov15_V4.0.xlsx")

    sheet = wb.sheet_by_index(1)

    keys = [sheet.cell(0, 5).value for col_index in xrange(sheet.ncols)]

    dict_list = []
    for rownum in range(sheet.nrows):
        d = {keys[col_index]: sheet.cell(0, 5).value 
        for col_index in xrange(sheet.ncols)}:
            dict_list.append(d)

The field that I want to use as key is column 5 and the values are columns #16 and #17 as an array value for each key...

Answer 1

Use this command

row_slice(rowx, start_colx=0, end_colx=None)

Returns a slice of the Cell objects in the given row.

Answer 2

Some issues in your code -

1. keys = [sheet.cell(0, 5).value for col_index in xrange(sheet.ncols)] - This always takes the keys as the value in the first row and 6th column (Rows and columns are 0 indexed.)

2. d = {keys[col_index]: sheet.cell(0, 5).value - This is not even valid python syntax

You can just loop over all the rows, take column index 4 (5th column) as key and the rest in a list and add that to a dictionary, Example -

import xlrd
from xlrd import open_workbook
import arcpy

wb = open_workbook ("c:\\Users\\Admin\\Documents\\Marion\\Courses\\GEOG485\\FinalProject\\Data\\ExcelFiles\\Belize_Culvert_Nov15_V4.0.xlsx")

sheet = wb.sheet_by_index(1)
sheetdict = {}
for rownum in range(sheet.nrows):
    sheetdict[sheet.cell(rownum,4)] = [sheet.cell(rownum,15),sheet.cell(rownum,16)]

In the end, sheetdict has the required dictionary.