如何在读取csv文件时修复非法换行值

Question

I have had trouble reading a .csv file using Python 3.7. When I wrote:

import csv
with open ('iris.csv', newline =' ') as csv_file:
    rows = csv.reader(csv_file)
    for row in rows:
        print(row)

and ran the code, it just says:

ValueError                                Traceback (most recent call last)
<ipython-input-2-42d17202da4e> in <module>()
      1 import csv
----> 2 with open ('iris.csv', newline =' ') as csv_file:
      3     rows = csv.reader(csv_file)
      4     for row in rows:
      5         print(row)

ValueError: illegal newline value:  

How can I fix this problem? And why is ' ' has an illegal value? I expcted it would be like:

['sepal_length', 'sepal_width', 'petal_length', 'petal_width', 'species']
['5.1', '3.5', '1.4', '0.2', 'setosa']
['4.9', '3', '1.4', '0.2', 'setosa']
['4.7', '3.2', '1.3', '0.2', 'setosa']
['4.6', '3.1', '1.5', '0.2', 'setosa']

Thanks!

Answer 1

From the docs : https://docs.python.org/3/library/functions.html#open

newline controls how universal newlines mode works (it only applies to text mode). It can be None, '', '\\n', '\\r', and '\\r\\n'.

In your case, newline =' ' is invalid since it is not one of the characters listed in the values in the docs.

I think you got confused with a csv delimiter in csv.reader , which is what separates two values in a csv file

Dialect.delimiter
A one-character string used to separate fields. It defaults to ','.

Example

a,b,c,d
e,f,g,h

Based on what your delimiter is, you can specify that in the delimiter field while reading the csv

rows = csv.reader(csv_file, delimiter="<your_delimiter>")