将数据保存到 Pandas 中的多个 csv 文件

Question

I have this data from a .gov site:

import pandas as pd
import io
import requests
url="https://download.bls.gov/pub/time.series/la/la.data.64.County"
s=requests.get(url).content
c=pd.read_csv(io.StringIO(s.decode('utf-8')))

The number of rows is 4942096. I want to get all these into multiple csv files.

I know how to get the first million as so:

c.to_csv('nick.csv', index = False, chunksize = 1000000)

How do I get the rest?

Answer 1

you can loop through the file and save it as so :

filename = io.StringIO(s.decode('utf-8'))
# ^ not tested this but assuming it would work for readability sake. 

chunk_size = 10 ** 6
for chunk in pd.read_csv(filename, chunksize=chunk_size):
    chunk.to_csv('nick.csv.gz',compression='gzip',index=False)

you'll need to add some sort of naming convention otherwise you will write over the file. I've also added in the gzip compression which significantly speeds up write times.

i'd just add a counter personally

chunk_size = 10 ** 6
counter = 0
for chunk in pd.read_csv(filename, chunksize=chunk_size):
    counter = counter + 1
    chunk.to_csv(f'nick_{str(counter)}.csv.gz',compression='gzip',index=False)