将数据写入CSV文件Python

Question

我的数据如下所示

['[\'Patient, A\', \'G\', \'P\', \'RNA\']']

无论括号，引号和反斜杠如何，我都想用“，”分隔数据，然后将其写入CSV文件，如下所示

Patient,A,G,P,RNA

提及定界符='，'并没有帮助。 输出文件如下所示

['Patient, A','G','P','RNA']

全部放在一个单元格中。 我想将它们分成多列。 我怎样才能做到这一点？

编辑-提及quotechar='|' 将它们分成不同的单元格，但现在看起来像

|['Patient, A','G','P','RNA']|

编辑-

out_file_handle = csv.writer(out_file, quotechar='|', lineterminator='\n', delimiter = ",")
data = ''.join(mydict.get(word.lower(), word) for word in re.split('(\W+)', transposed))
data = [data,]
out_file_handle.writerow(data)

转置：

['Patient, A','G','P','RNA']

数据：

['[\'Patient, A\', \'G\', \'P\', \'RNA\']']

并且它具有多行，以上是整个数据中的行之一。

Answer 1

首先，需要通过将字符串作为CSV文件处理在内存中，将此数据读入Python数组中：

from StringIO import StringIO
import csv
data = ['[\'Patient, A\', \'G\', \'P\', \'RNA\']']
clean_data = list(csv.reader( StringIO(data[0]) ))

但是输出仍然是单个字符串，因为它甚至不是格式正确的CSV！ 在那种情况下，最好的办法可能是过滤掉所有这些垃圾字符？

import re
clean_data = re.sub("[\[\]']","",data[0])

现在data [0]是'Patient, A, G, P, RNA' ，这是干净的CSV，您可以直接将其写入文件。

Answer 2

Python有一个CSV编写器。 从开始

import csv

然后尝试这样的事情

with open('new.csv', 'wb') as write_file:
    file_writer = csv.writer(write_file)
    for i in range(data):
        file_writer.writerow([x for x in data[i]])

编辑：

您可能需要先对数据进行一些处理，然后再进行写入，因为它看起来像是字符串，而不是列表。 尝试使用split（）函数

list = data.split()

Answer 3

如果您要执行的操作是以['[\\'Patient, A\\', \\'G\\', \\'P\\', \\'RNA\\']']的形式写入数据，将这些字符串组成的数组归档，那么这实际上是一个分为两个部分的问题。

第一个是如何将数据分离为正确的格式，然后第二个是将其写入文件。

如果那是数据的形式，那么对于每一行，这样的事情都应该起作用（将其转换为正确的格式）：

data = ['[\'Patient, A\', \'G\', \'P\', \'RNA\']', ...]
newData = [entry.replace("\'", "")[1:-1].split(",") for entry in data]

将以以下形式为您提供数据：

[["Patient", "A", "G", "P", "RNA"], ...]

然后您可以按照其他答案中的建议将其写入文件；

with open('new.csv', 'wb') as write_file:
  file_writer = csv.writer(write_file)
  for dataEntry in range(newData ):
    file_writer.writerow(dataEntry)

如果您实际上并不关心在本轮中使用数据，而只想清理它，则可以执行data.replace("\\'", "")[1:-1] ，然后将其写入文件字符串。

[1:-1]位仅用于删除前和后方括号。

Answer 4

"""
                             SAVING DATA INTO CSV FORMAT
    * This format is used for many purposes, mainly for deep learning.
    * This type of file can be used to view data in MS Excel or any similar 
      Application
"""
# == Imports ===================================================================

import csv
import sys

# == Initialisation Function ===================================================

def initialise_csvlog(filename, fields):
    """
    Initilisation this function before using the Inserction function

    * This Function checks the data before adding new one in order to maintain
      perfect mechanisum of insertion
    * It check the file if not exists then it creates a new one
    * if it exists then it proceeds with getting fields

    Parameters
    ----------
    filename : String
        Filename along with directory which need to be created
    Fields : List
        Colomns That need to be initialised

    """
    try :
        with open(filename,'r') as csvfile:
            csvreader = csv.reader(csvfile)
            fields = csvreader.next()
            print("Data Already Exists")
            sys.exit("Please Create a new empty file")
            # print fields  
    except :
        with open(filename,'w') as csvfile:

            csvwriter = csv.writer(csvfile)
            csvwriter.writerow(fields)

# == Data Insertion Function ===================================================

def write_data_csv(filename, row_data):
    """
    This Function save the Row Data into the CSV Created
    * This adds the row data that is Double Listed

    Parameters
    ----------
    filename : String
        Filename along with directory which need to be created
    row_data : List
        Double Listed consisting of row data and column elements in a list  
    """
    with open(filename,'a') as csvfile:

        csvwriter = csv.writer(csvfile)
        csvwriter.writerows(row_data)

if __name__ == '__main__':
    """
    This function is used to test the Feature Run it independently

    NOTE: DATA IN row_data MUST BE IN THE FOLLOWING DOUBLE LISTED AS SHOWN
    """
    filename = "TestCSV.csv"
    fields = ["sno","Name","Work","Department"]
    #Init
    initialise_csvlog(filename,fields)
    #Add Data
    row_data = [["1","Jhon","Coder","Pythonic"]]
    write_data_csv(filename,row_data)

# == END =======================================================================

阅读该模块，您可以开始使用CSV并在Excel或任何类似应用程序中查看数据（libreoffice中的calc）

注意：请记住要放置要重复列出的数据列表，如__main__函数（row_data）所示。