如何在CSV文件上每10行进行迭代

Question

with open(example.csv') as csvfile:
    readCSV = csv.reader(csvfile, delimiter=',')

    for row in readCSV:
        Do something.

I need to skip every 10 lines in for loop, but doing readCSV[::10] won't work.

Answer 1

with open('example.csv') as csvfile:
    readCSV = csv.reader(csvfile, delimiter=',')
    for i, row in enumerate(readCSV):
        if i % 10 == 0:
            # do stuff with every 10th row

Answer 2

This boils down to iterating over every 10 ^th element from a generator, which can be done with itertools.islice :

import itertools
import csv

with open('example.csv') as csvfile:
    readCSV = csv.reader(csvfile, delimiter=',')

    for row in itertools.islice(readCSV, None, None, 10):
        # Do something.

This does the equivalent of slicing a list (as in list[::10] ) on a generator.

Answer 3

Keep track of the index with an iterator

with open(example.csv') as csvfile:
    readCSV = csv.reader(csvfile, delimiter=',')
    i = 0
    for row in readCSV:
        if i%10 = 0:
            continue
        Do something.
        i += 1

Answer 4

You could add this to

count = 0
for line in f:
    count+=1
    if count % 10 == 0: 
        print line