Question

我编写了以下代码：

import sys, csv, operator
data = csv.reader(open('books.csv'),delimiter=',')
header = next(data)
print (header)
sortedlist = sorted(data, key=operator.itemgetter(1))
with open("books_sort.csv", "wb") as f:
#          fileWriter = csv.writer(f, delimiter=',')
           fileWriter = csv.writer(f)
#           fileWriter.writerows(header)
#           fileWriter.writerows(sortedlist)

           for row in sortedlist:
              print (row)
#             f.writerows(row)

此代码的目的是获取一个内容在各列中的文件，并仅根据第二列将其按字母顺序排列。然后，它将所需的结果输出到新文件中。我上面的代码可以打印所需的结果，但是当我尝试使其输出包含该结果的新文件时，它将无法正常工作。您可以在上面的注释中看到我尝试编写新文件的部分。伙计们对此有什么想法吗？在你们中的任何人说使用熊猫是更简单的方法之前，我明确不允许这样做。以下是我文件的内容：

Title,            Author,        Publisher,  Year,  ISBN-10,   ISBN-13
Automate the...,  Al Sweigart,   No Sta...,  2015,  15932...,  978-15932...
Dive into Py...,  Mark Pilgr..., Apress,     2009,  14302...,  978-14302...
"Python Cook...,  "David Bea..., O'Reil...,  2013,  14493...,  978-14493...
Think Python...,  Allen B. D..., O'Reil...,  2015,  14919...,  978-14919...
"Fluent Pyth...,  Luciano Ra..., O'Reil...,  2015,  14919...,  978-14919...

Answer 1

看来您正在使这项工作变得不必要。首先，让我们清理示例数据，因为不匹配的双引号会使cvs.reader混乱：

Title,Author,Publisher,Year,ISBN-10,ISBN-13
Automate the...,Al Sweigart,No Sta...,2015,15932...,978-15932...
Dive into Py...,Mark Pilgr...,Apress,2009,14302...,978-14302...
"Python Coo...",David Beaz...,O'Reil...,2013,14493...,978-14493...
Think Python...,Allen B. D...,O'Reil...,2015,14919..., 978-14919...
"Fluent Pyt...",Luciano Ra...,O'Reil...,2015,14919...,978-14919...

接下来，让我们根据cvs模块文档构建一个程序：

import csv
import operator

data = csv.reader(open('books.csv', newline=''), delimiter=',')

header = next(data)

sortedlist = sorted(data, key=operator.itemgetter(1))

with open("books_sorted.csv", "w", newline='') as csvfile:
    cvsWriter = csv.writer(csvfile, delimiter=',')

    cvsWriter.writerow(header)

    cvsWriter.writerows(sortedlist)

哪个会生成包含以下内容的输出文件：

Title,Author,Publisher,Year,ISBN-10,ISBN-13
Automate the...,Al Sweigart,No Sta...,2015,15932...,978-15932...
Think Python...,Allen B. D...,O'Reil...,2015,14919..., 978-14919...
Python Coo...,David Beaz...,O'Reil...,2013,14493...,978-14493...
Fluent Pyt...,Luciano Ra...,O'Reil...,2015,14919...,978-14919...
Dive into Py...,Mark Pilgr...,Apress,2009,14302...,978-14302...

缺少双引号，但希望正确。在注释掉的代码中，您在单行中调用了writerows()

#fileWriter.writerows(header)

for row in sortedlist:
              print (row)
#             f.writerows(row)

我们不应该期望它起作用。在这里，您将改用writerow()。

使用Python将CSV输入文件更改写入CSV输出文件

1 个答案: