Python 字典到数据帧 - DataFrame 构造函数未正确调用

Question

我使用了一个字典，其中包含 source-destination 作为键，messages 作为值。它循环遍历第一个数据帧，对于每个问题，将发布第一条消息的人存储为目标，将发布第二条消息的人存储为源，在字典中的键“源-目标”处添加一个计数器。

现在我正在尝试将字典转换为数据帧，但收到此错误消息
ValueError:如果使用所有标量值，则必须传递索引。

import pandas as pd
from itertools import permutations

df = pd.read_csv('example.csv', sep=';', engine='python')

messages = {}  # the dictionary where results is going to be stored
student= set()
destination = False  # a simple boolean to make sure message 2 follows message 1

for row in df:  # iterate over the dataframe
    student.add(row[2])  # collect students' name
    if row[1] == 1:  # if it is an initial message
        destination = row[2]  # we store students as destination
    elif row[1] == 2 and destination:  # if this is a second message
        source = row[2]  # store student as source
        key = source + "-" + destination  # construct a key based on source/destination
        if key not in messages:  # if the key is new to dictionary
            messages[key] = 1  # create the new entry
        else:  # otherwise
            messages[key] += 1  # add a counter to the existing entry
        destination = False  # reset destination

    else:
        destination = False  # reset destination

# add the pairs of source-destination who didn't interact in the dictionnary
for pair in permutations(student, 2):
    if "-".join(pair) not in messages:
        messages["-".join(pair)] = 0

 f1 = pd.DataFrame.from_dict(messages)
 print(f1)

知道为什么吗？

提前谢谢您。

Answer 1

您的代码中可能混合使用了制表符和空格。尝试删除所有制表符并用空格替换它们。

同样的问题:IndentationError: unindent does not match any outer indentation level