无法在 Python 3.7/Spyder/Anaconda 上运行 csv 模块

Question

I'm trying to open a CSV file on Python 3.7/Spyder/Anaconda IDE.

I want to learn how to import csv files either by using pandas and by using the csv libraries.

The following code worked well and a csvfile variable containing the data frame was created:

import pandas as pd
csvfile = pd.read_csv(r'C:\Users\Documents\PyLearning\data_file.csv', sep=',')

However I didn't get the same result with the csv module. After running the following code, nothing happend.

import csv
csvfile = open('data_file.csv', 'rb')
reader = csv.reader(csvfile)

I got no error message but no variable was created.

I would like to some help to understand why this is happening.

EDIT: It seems csv module was replaced by unicodecsv module at more recent python versions https://pypi.org/project/unicodecsv/

Answer 1

If you're looking for how to use a builtin Python module (the csv module, for example), I would recommend looking at the official Python documentation.

You can find the documentation for the csv module here .

Here's the first example they give of reading a csv file (see https://docs.python.org/3/library/csv.html#examples ):

with open('some.csv', newline='') as f:
    reader = csv.reader(f)
    for row in reader:
        print(row)

In the loop, you can access row to store it in whatever data structure you prefer.

For example, to put it in all in a list:

with open('some.csv', newline='') as f:
    reader = csv.reader(f)
    data = [row for row in reader]
print(data)

Answer 2

The beauty of using pandas' read_csv is that it automatically and most importantly quickly converts said csv into a usable dataframe.

using csv.reader simply refers to the csv in question but you would have to call an iterator to get a result.

ie: (from https://docs.python.org/3/library/csv.html )

>>> import csv
>>> with open('eggs.csv', newline='') as csvfile:
...     spamreader = csv.reader(csvfile, delimiter=' ', quotechar='|')
...     for row in spamreader:
...         print(', '.join(row))
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