从标准输入替换csv中的特殊字符

Question

我需要创建一个程序，输出的行的列2的== 'Kashiwa“的值。在csv格式的行是通过标准输入提供的。我还需要删除"，”‘“，换行符和其他特殊字符，如果他们包括在”名称“列的值。以下是输入的示例：

2
Kashiwa
Name,Campus,LabName
Shin MORISHIA,Kashiwa,Laboratory of Omics
Kioshi ASAy,Kashiwa,Laboratory of Genome Informatics
Yukihido Tomari,Yayoi,Laboratory of RNA Function
Masao Kanobe ,Kashiwa,Laboratory of Large-Scale Bioinformatics

下面是我的代码：

 #!usr/bin/env python3

 import sys
 import csv

 data = sys.stdin.readlines()

 chars = ('$','%','^','*', '\n', '"', "," )
 for line in data:
     for c in chars:
         line = ''.join(line.split(c))

 reader = csv.reader(data)
 next(reader)
 next(reader)
 print(",".join(next(reader)))

 for row in reader:

      if row[1] == 'Kashiwa':

         print(",".join(row))

我的程序似乎没有从列名的值中删除特殊字符。我该怎么做呢？

Answer 1

在data = sys.stdin.readlines()之后，data是一个字符串列表。

你是这样处理它的：

 for line in data:                      # ok line is a variable pointing to a string from data
     for c in chars:                    # ok you process all of your special characters
         line = ''.join(line.split(c))  # line is now a brand new clean string...
                                        #  that you forget at once without changing data!

无论如何，Python字符串是一个不可变的对象，所以您必须更改列表以包含新行：

 for i, line in enumerate(data):        # ok line is a variable pointing to a string from data
     for c in chars:                    # ok you process all of your special characters
         line = ''.join(line.split(c))  # line is now a brand new clean string...
     data[i] = line                 #  and data uses this new line

但如果您只想清理第一列，则不需要将所有内容都加载到内存中：

 #!usr/bin/env python3

 import sys
 import csv

 next(sys.stdin)
 next(sys.stdin)
 print(next(sys.stdin))
 reader = csv.reader(sys.stdin)

 chars = ('$','%','^','*', '\n', '"', "," )

 for row in reader:
     line = row[0]
     for c in chars:
         line = ''.join(line.split(c))
     row[0] = line

     if row[1] == 'Kashiwa':
         print(",".join(row))

Answer 2

得到的印象是，你正在看一些东大的页面。这就是我得到的。我将csv文件与您给我们的数据放在一起，使其更易于阅读。

import pandas

chars = ['$','%','^','*', '\n', '"', "," ]
dataframe = pandas.read_csv("data.csv")
dataframe = dataframe[dataframe.Campus == 'Kashiwa']

for c in chars:
    dataframe["Name"] = dataframe["Name"].str.replace(c, '')
print(dataframe)

我在这里使用的是pandas，它在快速读取csvs时是最好的，并且当你检查chars表中是否存在字符时，它有方便的方法来更改所有行。在第三行中，您可以看到，如果实验室不在岸和校区，也可以很容易地删除所有行。我试过了，它起作用了。希望这能有所帮助！

csv文件如下所示：

Name,Campus,LabName
Shi$n MORISHIA,Kashiwa,Laboratory of Omics
Kio%s$hi ASAy,Kashiwa,Laboratory of Genome Informatics
Yuki%hi**do Tomari,Kashiwa,Laboratory of RNA Function
Masao Kanobe ,Kashiwa,Laboratory of Large-Scale Bioinformatics

下面是输出：

     Name            Campus                         LabName
0    Shin MORISHIA  Kashiwa                       Laboratory of Omics
1      Kioshi ASAy  Kashiwa          Laboratory of Genome Informatics
2  Yukihido Tomari  Kashiwa                Laboratory of RNA Function
3    Masao Kanobe   Kashiwa  Laboratory of Large-Scale Bioinformatics