通过 Python 将头文件添加到 csv 文件

我编写了一个合并两个 csv 文件的 Python 脚本，现在我想向最终的 csv 添加一个头文件。我尝试了下面的建议报告 给你和我得到了以下错误: expected string, float found。修复这个问题最简单的方法是什么？

下面是我使用的代码:

import csv


with open('combined_file.csv', 'w', newline='') as outcsv:
writer = csv.DictWriter(outcsv, fieldnames = ["Date", "temperature 1", "Temperature 2"])
writer.writeheader()


with open('t1.csv', 'r', newline='') as incsv:
reader = csv.reader(incsv)
writer.writerows(row + [0.0] for row in reader)


with open('t2.csv', 'r', newline='') as incsv:
reader = csv.reader(incsv)
writer.writerows(row[:1] + [0.0] + row[1:] for row in reader)
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最佳答案

The DictWriter() class expects dictionaries for each row. If all you wanted to do was write an initial header, use a regular csv.writer() and pass in a simple row for the header:

import csv


with open('combined_file.csv', 'w', newline='') as outcsv:
writer = csv.writer(outcsv)
writer.writerow(["Date", "temperature 1", "Temperature 2"])


with open('t1.csv', 'r', newline='') as incsv:
reader = csv.reader(incsv)
writer.writerows(row + [0.0] for row in reader)


with open('t2.csv', 'r', newline='') as incsv:
reader = csv.reader(incsv)
writer.writerows(row[:1] + [0.0] + row[1:] for row in reader)

The alternative would be to generate dictionaries when copying across your data:

import csv


with open('combined_file.csv', 'w', newline='') as outcsv:
writer = csv.DictWriter(outcsv, fieldnames = ["Date", "temperature 1", "Temperature 2"])
writer.writeheader()


with open('t1.csv', 'r', newline='') as incsv:
reader = csv.reader(incsv)
writer.writerows({'Date': row[0], 'temperature 1': row[1], 'temperature 2': 0.0} for row in reader)


with open('t2.csv', 'r', newline='') as incsv:
reader = csv.reader(incsv)
writer.writerows({'Date': row[0], 'temperature 1': 0.0, 'temperature 2': row[1]} for row in reader)
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You just add one additional row before you execute the loop. This row contains your CSV file header name.

schema = ['a','b','c','b']
row = 4
generators = ['A','B','C','D']
with open('test.csv','wb') as csvfile:
writer = csv.writer(csvfile, delimiter=delimiter)
# Gives the header name row into csv
writer.writerow([g for g in schema])
#Data add in csv file
for x in xrange(rows):
writer.writerow([g() for g in generators])
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This worked for me. 

header = ['row1', 'row2', 'row3']
some_list = [1, 2, 3]
with open('test.csv', 'wt', newline ='') as file:
writer = csv.writer(file, delimiter=',')
writer.writerow(i for i in header)
for j in some_list:
writer.writerow(j)
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Would not this be simple that if we are creating file that time only we add header if we are not than append data to it..

  conso_file_path = 'your_folder_path\your_file.csv'
# Create File
if not os.path.exists(conso_file_path):
print("No File")
header = ['col_name 1', 'col_name 1', 'col_name 3', 'col_name4']
with open(conso_file_path, 'w') as f:
writer = csv.writer(f)
writer.writerow(header)

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