Python 3统计CSV中的行数

Question

从2.7迁移后，我在Python 3环境中很难获得行数。几次尝试后，返回的行数为1。我如何绕过一个DeprecationWarning：'U'模式在python 3中被弃用？

             input_file = open("test.csv","rU")
             reader_file = csv.reader(input_file)
             value = len(list(reader_file))

在使用Python3的情况下，我尝试了以下方法，但我仍然坚持使用1。

             input_file = open("test.csv","rb")
             reader_file = csv.reader(input_file)
             value = len(list(reader_file))

Answer 1

input_file = open("test.csv","rb") #rb is a read-in-binary format and 
#you can't count the number of row from binary format file

with open("text.csv",'r') as f:
file = f.readlines()
print(len(file))

# Data in my text file
# a
# b
# c
# d
# e

#The output of above code is 
#5 means number of rows is 5 

Answer 2

如果您使用的是pandas，那么您可以轻松地做到这一点，而无需编写太多代码。

import pandas as pd

df = pd.read_csv('filename.csv')

## Fastest would be using length of index

print("Number of rows ", len(df.index))

## If you want the column and row count then

row_count, column_count = df.shape

print("Number of rows ", row_count)
print("Number of columns ", column_count)