将循环应用于 CSV 文件的列

Question

我是 Python 的初学者。 我有一个带有单列数字的 csv 文件，我必须找到所有大于前一个和下一个数字的数字。 我不明白如何将 for 循环应用于文件列。

我尝试的代码如下：

import pandas as pd

pf = pd.read_csv(r'C:\Users\Fra\Desktop\IO.csv')
print(pf)

results = []
for column in pf:
    for i in range(len(column)):
        if(x[i]>x[i-1] and x[i]>x[i+1]):
             results.append(x[i])

print(results)

Answer 1

假设您的文件具有以下格式：

4
7
5
3
4
...

您不必使用熊猫：

bucket = []

with open(filename) as f:
    for line in f:
        item = int(line)
        bucket.append(item)

results = []

for i in range(1, len(bucket) - 1): # iterate from second to the second last item
    a = bucket[i-1]
    b = bucket[i]
    c = bucket[i+1]
    if b > a and b > c:
        results.append(b)

如果您真的想使用熊猫：

import pandas as pd

pf = pd.read_csv(filename)
pf.astype(int)

results = []

for i in range(1, len(pf) - 1): # iterate from second to the second last item
    a = pf.loc[i-1][0]    # 0 here is the header name
    b = pf.loc[i][0]      # As we have no header, it is 0, indicating the first column
    c = pf.loc[i+1][0]

    if b > a and b > c:
        results.append(b)

参考： 如何从 dataframe 的单元格中获取值？