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[10]] += 1
with open('/pythonwork/thefile_subset11.csv', 'w') as outfile:
writer = csv.writer(outfile)
for row in data:
if counter[row[10]] >= 504:
writer.writerow(row)
这段代码读取file.csv，进行修改，并将结果写入到file_subset1。
然而，当我在Microsoft Excel中打开结果csv时，每条记录后都有一个额外的空行!
有没有办法让它不放额外的空行?
当前回答
我使用writerow
def write_csv(writer, var1, var2, var3, var4):
"""
write four variables into a csv file
"""
writer.writerow([var1, var2, var3, var4])
numbers=set([1,2,3,4,5,6,7,2,4,6,8,10,12,14,16])
rules = list(permutations(numbers, 4))
#print(rules)
selection=[]
with open("count.csv", 'w',newline='') as csvfile:
writer = csv.writer(csvfile)
for rule in rules:
number1,number2,number3,number4=rule
if ((number1+number2+number3+number4)%5==0):
#print(rule)
selection.append(rule)
write_csv(writer,number1,number2,number3,number4)
其他回答
在使用Python 3时，可以通过使用codecs模块来避免空行。正如文档中所述，文件是以二进制模式打开的，因此不需要更改换行符kwarg。我最近遇到了同样的问题，这对我来说很有效:
with codecs.open( csv_file, mode='w', encoding='utf-8') as out_csv:
csv_out_file = csv.DictWriter(out_csv)
with open(destPath+'\\'+csvXML, 'a+') as csvFile:
writer = csv.writer(csvFile, delimiter=';', lineterminator='\r')
writer.writerows(xmlList)
lineterminator='\r'"允许传递到下一行，两行之间没有空行。
简单的答案是csv文件应该总是以二进制模式打开，无论是输入还是输出，否则在Windows上就会出现行结束的问题。具体来说，在输出时，csv模块将写入\r\n(标准的csv行结束符)，然后(在文本模式下)运行时将用\r\n (Windows标准的行结束符)替换\n，给出结果\r\r\n。
摆弄线终结者不是解决方案。
使用下面定义的方法将数据写入CSV文件。
open('outputFile.csv', 'a',newline='')
只需在open方法中添加一个额外的newline= "参数:
def writePhoneSpecsToCSV():
rowData=["field1", "field2"]
with open('outputFile.csv', 'a',newline='') as csv_file:
writer = csv.writer(csv_file)
writer.writerow(rowData)
这将写入CSV行，而无需创建额外的行!
借用这个答案，似乎最干净的解决方案是使用io.TextIOWrapper。我为自己解决了这个问题:
from io import TextIOWrapper
...
with open(filename, 'wb') as csvfile, TextIOWrapper(csvfile, encoding='utf-8', newline='') as wrapper:
csvwriter = csv.writer(wrapper)
for data_row in data:
csvwriter.writerow(data_row)
上面的答案与Python 2不兼容。为了具有兼容性，我认为只需要将所有的写入逻辑包装在if块中:
if sys.version_info < (3,):
# Python 2 way of handling CSVs
else:
# The above logic
