使用Python将结果保存到csv文件


Save results to csv file with Python

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import csv

with open('test.csv', 'rb') as f:
  data = list(csv.reader(f))

import collections
counter = collections.defaultdict(int)
for row in data:
    counter[row[1]] += 1
for row in data:
    if counter[row[1]] >= 4:
      writer = csv.writer(open("test1.csv","wb"))
      writer.writerows(row)

我得到了奇怪的输出！这个代码有什么问题？

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我知道问题是关于您的"csv"包实现，但对于您的信息，有一些更简单的选项，例如numpy。

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import numpy as np
np.savetxt('data.csv', (col1_array, col2_array, col3_array), delimiter=',')

(为了子孙后代，这个答案在6年后公布。)

在另一个类似于您所问的情况下，假设您有两个这样的列：

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names = ['Player Name', 'Foo', 'Bar']
scores = ['Score', 250, 500]

你可以这样保存它：

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np.savetxt('scores.csv', [p for p in zip(names, scores)], delimiter=',', fmt='%s')

scores.csv如下：

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Player Name,Score
Foo,250
Bar,500

使用csv.writer：

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import csv

with open('thefile.csv', 'rb') as f:
  data = list(csv.reader(f))

import collections
counter = collections.defaultdict(int)
for row in data:
    counter[row[0]] += 1


writer = csv.writer(open("/path/to/my/csv/file", 'w'))
for row in data:
    if counter[row[0]] >= 4:
        writer.writerow(row)
相关讨论

您可以关闭不是csv.writer对象的文件，它应该是：

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f = open(fileName,"wb")
writer = csv.writer(f)
String[] entries ="first*second*third".split("*");
writer.writerows(entries)
f.close()

一个简单的例子是：

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writer = csv.writer(open("filename.csv","wb"))
String[] entries ="first#second#third".split("#");
writer.writerows(entries)
writer.close()
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我就是这样做的

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 import csv
    file = open('???.csv', 'r')
    read = csv.reader(file)
    for column in read:
            file = open('???.csv', 'r')
            read = csv.reader(file)
            file.close()
            file = open('????.csv', 'a', newline='')
            write = csv.writer(file, delimiter =",")
            write.writerow((, ))
            file.close()
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这将提供准确的输出

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import csv

import collections

with open('file.csv', 'rb') as f:

  data = list(csv.reader(f))

counter = collections.defaultdict(int)

for row in data:

    counter[row[0]] += 1

writer = csv.writer(open("file1.csv", 'w'))

for row in data:

    if counter[row[0]] >= 1:

        writer.writerow(row)
相关讨论