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Python CSV字符串到数组

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问题：Python CSV字符串到数组
回答 0
回答 1
回答 2
回答 3
回答 4
回答 5
回答 6
回答 7
回答 8
回答 9

问题：Python CSV字符串到数组

有人知道一个简单的库或函数来解析csv编码的字符串并将其转换为数组或字典吗？

我不认为我想要内置的csv模块，因为在所有示例中，我看到的都是文件路径，而不是字符串。

点击查看英文原文

Anyone know of a simple library or function to parse a csv encoded string and turn it into an array or dictionary?

I don’t think I want the built in csv module because in all the examples I’ve seen that takes filepaths, not strings.

回答 0

您可以使用将字符串转换为文件对象io.StringIO，然后将其传递给csv模块：

from io import StringIO
import csv

scsv = """text,with,Polish,non-Latin,letters
1,2,3,4,5,6
a,b,c,d,e,f
gęś,zółty,wąż,idzie,wąską,dróżką,
"""

f = StringIO(scsv)
reader = csv.reader(f, delimiter=',')
for row in reader:
    print('\t'.join(row))

带有split()换行符的简单版本：

reader = csv.reader(scsv.split('\n'), delimiter=',')
for row in reader:
    print('\t'.join(row))

或者，您可以split()使用\n分隔符将此字符串简单地分成几行，然后将split()每一行变成值，但是这种方式您必须知道引号，因此csv首选使用module。

在Python 2上，您必须导入StringIO为

from StringIO import StringIO

代替。

点击查看英文原文

You can convert a string to a file object using io.StringIO and then pass that to the csv module:

from io import StringIO
import csv

scsv = """text,with,Polish,non-Latin,letters
1,2,3,4,5,6
a,b,c,d,e,f
gęś,zółty,wąż,idzie,wąską,dróżką,
"""

f = StringIO(scsv)
reader = csv.reader(f, delimiter=',')
for row in reader:
    print('\t'.join(row))

simpler version with split() on newlines:

reader = csv.reader(scsv.split('\n'), delimiter=',')
for row in reader:
    print('\t'.join(row))

Or you can simply split() this string into lines using \n as separator, and then split() each line into values, but this way you must be aware of quoting, so using csv module is preferred.

On Python 2 you have to import StringIO as

from StringIO import StringIO

instead.

回答 1

简单-csv模块也可以使用列表：

>>> a=["1,2,3","4,5,6"]  # or a = "1,2,3\n4,5,6".split('\n')
>>> import csv
>>> x = csv.reader(a)
>>> list(x)
[['1', '2', '3'], ['4', '5', '6']]
点击查看英文原文

Simple – the csv module works with lists, too:

>>> a=["1,2,3","4,5,6"]  # or a = "1,2,3\n4,5,6".split('\n')
>>> import csv
>>> x = csv.reader(a)
>>> list(x)
[['1', '2', '3'], ['4', '5', '6']]

回答 2

csv.reader() https://docs.python.org/2/library/csv.html的官方文档 非常有帮助，它说

文件对象和列表对象都适合

import csv

text = """1,2,3
a,b,c
d,e,f"""

lines = text.splitlines()
reader = csv.reader(lines, delimiter=',')
for row in reader:
    print('\t'.join(row))
点击查看英文原文

The official doc for csv.reader() https://docs.python.org/2/library/csv.html is very helpful, which says

file objects and list objects are both suitable

import csv

text = """1,2,3
a,b,c
d,e,f"""

lines = text.splitlines()
reader = csv.reader(lines, delimiter=',')
for row in reader:
    print('\t'.join(row))

回答 3

>>> a = "1,2"
>>> a
'1,2'
>>> b = a.split(",")
>>> b
['1', '2']

解析CSV文件：

f = open(file.csv, "r")
lines = f.read().split("\n") # "\r\n" if needed

for line in lines:
    if line != "": # add other needed checks to skip titles
        cols = line.split(",")
        print cols
点击查看英文原文 
>>> a = "1,2"
>>> a
'1,2'
>>> b = a.split(",")
>>> b
['1', '2']

To parse a CSV file:

f = open(file.csv, "r")
lines = f.read().split("\n") # "\r\n" if needed

for line in lines:
    if line != "": # add other needed checks to skip titles
        cols = line.split(",")
        print cols

回答 4

正如其他人已经指出的那样，Python包含一个用于读取和写入CSV文件的模块。只要输入字符保持在ASCII限制内，它就可以很好地工作。如果您要处理其他编码，则需要做更多的工作。

csv模块的Python文档实现了csv.reader的扩展，该扩展使用相同的接口，但可以处理其他编码并返回unicode字符串。只需复制并粘贴文档中的代码即可。之后，您可以像这样处理CSV文件：

with open("some.csv", "rb") as csvFile: 
    for row in UnicodeReader(csvFile, encoding="iso-8859-15"):
        print row
点击查看英文原文

As others have already pointed out, Python includes a module to read and write CSV files. It works pretty well as long as the input characters stay within ASCII limits. In case you want to process other encodings, more work is needed.

The Python documentation for the csv module implements an extension of csv.reader, which uses the same interface but can handle other encodings and returns unicode strings. Just copy and paste the code from the documentation. After that, you can process a CSV file like this:

with open("some.csv", "rb") as csvFile: 
    for row in UnicodeReader(csvFile, encoding="iso-8859-15"):
        print row

回答 5

根据文档：

尽管该模块不直接支持解析字符串，但可以轻松实现：

import csv
for row in csv.reader(['one,two,three']):
    print row

只需将您的字符串转换为单个元素列表即可。

当这个例子在文档中明确时，导入StringIO对我来说似乎有点多余。

点击查看英文原文

Per the documentation:

And while the module doesn’t directly support parsing strings, it can easily be done:

import csv
for row in csv.reader(['one,two,three']):
    print row

Just turn your string into a single element list.

Importing StringIO seems a bit excessive to me when this example is explicitly in the docs.

回答 6

https://docs.python.org/2/library/csv.html?highlight=csv#csv.reader

csvfile可以是任何支持迭代器协议的对象，并且每次调用其next（）方法时都会返回一个字符串

因此，一个StringIO.StringIO()，str.splitlines()甚至一个生成器都很好。

点击查看英文原文

https://docs.python.org/2/library/csv.html?highlight=csv#csv.reader

csvfile can be any object which supports the iterator protocol and returns a string each time its next() method is called

Thus, a StringIO.StringIO(), str.splitlines() or even a generator are all good.

回答 7

这是一个替代解决方案：

>>> import pyexcel as pe
>>> text="""1,2,3
... a,b,c
... d,e,f"""
>>> s = pe.load_from_memory('csv', text)
>>> s
Sheet Name: csv
+---+---+---+
| 1 | 2 | 3 |
+---+---+---+
| a | b | c |
+---+---+---+
| d | e | f |
+---+---+---+
>>> s.to_array()
[[u'1', u'2', u'3'], [u'a', u'b', u'c'], [u'd', u'e', u'f']]

这是文档

点击查看英文原文

Here’s an alternative solution:

>>> import pyexcel as pe
>>> text="""1,2,3
... a,b,c
... d,e,f"""
>>> s = pe.load_from_memory('csv', text)
>>> s
Sheet Name: csv
+---+---+---+
| 1 | 2 | 3 |
+---+---+---+
| a | b | c |
+---+---+---+
| d | e | f |
+---+---+---+
>>> s.to_array()
[[u'1', u'2', u'3'], [u'a', u'b', u'c'], [u'd', u'e', u'f']]

Here’s the documentation

回答 8

使用此功能将csv加载到列表中

import csv

csvfile = open(myfile, 'r')
reader = csv.reader(csvfile, delimiter='\t')
my_list = list(reader)
print my_list
>>>[['1st_line', '0'],
    ['2nd_line', '0']]
点击查看英文原文

Use this to have a csv loaded into a list

import csv

csvfile = open(myfile, 'r')
reader = csv.reader(csvfile, delimiter='\t')
my_list = list(reader)
print my_list
>>>[['1st_line', '0'],
    ['2nd_line', '0']]

回答 9

Panda是功能强大且智能的库，可使用Python读取CSV

这里有一个简单的例子，我有example.zip文件，其中有四个文件。

EXAMPLE.zip
 -- example1.csv
 -- example1.txt
 -- example2.csv
 -- example2.txt

from zipfile import ZipFile
import pandas as pd


filepath = 'EXAMPLE.zip'
file_prefix = filepath[:-4].lower()

zipfile = ZipFile(filepath)
target_file = ''.join([file_prefix, '/', file_prefix, 1 , '.csv'])

df = pd.read_csv(zipfile.open(target_file))

print(df.head()) # print first five row of csv
print(df[COL_NAME]) # fetch the col_name data

有了数据后，您就可以操纵播放列表或其他格式。

点击查看英文原文

Panda is quite powerful and smart library reading CSV in Python

A simple example here, I have example.zip file with four files in it.

EXAMPLE.zip
 -- example1.csv
 -- example1.txt
 -- example2.csv
 -- example2.txt

from zipfile import ZipFile
import pandas as pd


filepath = 'EXAMPLE.zip'
file_prefix = filepath[:-4].lower()

zipfile = ZipFile(filepath)
target_file = ''.join([file_prefix, '/', file_prefix, 1 , '.csv'])

df = pd.read_csv(zipfile.open(target_file))

print(df.head()) # print first five row of csv
print(df[COL_NAME]) # fetch the col_name data

Once you have data you can manipulate to play with a list or other formats.