我如何跳过标题行并开始从第2行读取文件?
当前回答
# Open a connection to the file
with open('world_dev_ind.csv') as file:
# Skip the column names
file.readline()
# Initialize an empty dictionary: counts_dict
counts_dict = {}
# Process only the first 1000 rows
for j in range(0, 1000):
# Split the current line into a list: line
line = file.readline().split(',')
# Get the value for the first column: first_col
first_col = line[0]
# If the column value is in the dict, increment its value
if first_col in counts_dict.keys():
counts_dict[first_col] += 1
# Else, add to the dict and set value to 1
else:
counts_dict[first_col] = 1
# Print the resulting dictionary
print(counts_dict)
其他回答
# Open a connection to the file
with open('world_dev_ind.csv') as file:
# Skip the column names
file.readline()
# Initialize an empty dictionary: counts_dict
counts_dict = {}
# Process only the first 1000 rows
for j in range(0, 1000):
# Split the current line into a list: line
line = file.readline().split(',')
# Get the value for the first column: first_col
first_col = line[0]
# If the column value is in the dict, increment its value
if first_col in counts_dict.keys():
counts_dict[first_col] += 1
# Else, add to the dict and set value to 1
else:
counts_dict[first_col] = 1
# Print the resulting dictionary
print(counts_dict)
如果你想要第一行,然后你想对文件执行一些操作,这段代码将会很有帮助。
with open(filename , 'r') as f:
first_line = f.readline()
for line in f:
# Perform some operations
with open(fname) as f:
next(f)
for line in f:
#do something
如果您想从第2行开始读取多个CSV文件,这就像一个魅力
for files in csv_file_list:
with open(files, 'r') as r:
next(r) #skip headers
rr = csv.reader(r)
for row in rr:
#do something
(这是Parfait对另一个问题的部分回答)
如果切片可以在迭代器上工作……
from itertools import islice
with open(fname) as f:
for line in islice(f, 1, None):
pass
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