Question

我有4个报纸的4个数据框（newspaper1，newspaper2，newspaper3，newspaper4]）其中只有一列作者姓名。

现在，我想将这4个数据帧合并为一个，有5列：作者，以及报纸1，报纸2，报纸3，报纸4，其中包含1/0的值（作者为该报纸写作时为1）

import pandas as pd 

listOfMedia =[newspaper1,newspaper2,newspaper3,newspaper4]
merged = pd.DataFrame(columns=['author','newspaper1','newspaper2', 'newspaper4', 'newspaper4'])

尽管此循环可以实现我的预期（用名称填充合并的df author列）：

for item in listOfMedia:
    merged.author = item.author

我不知道如何用1/0值填充报纸栏...

for item in listOfMedia:
    if item == newspaper1:
        merged['newspaper1'] = '1'
    elif item == newspaper2:
        merged['newspaper2'] = '1'
    elif item == newspaper3:
        merged['newspaper3'] = '1'
    else:
        merged['newspaper4'] = '1'

我不断出错

在处理上述异常期间，发生了另一个异常： TypeError：attrib（）得到了意外的关键字参数'convert' 曾尝试向Google发送该错误，但并没有帮助我确定问题所在。我在这里想念什么？我还认为必须有一种更聪明的方法来填充报纸/作者矩阵，但是即使这样简单的方法似乎也无法弄清楚。我正在使用jupyter笔记本。

Answer 1

实际上，您将所有行设置为1，因此请使用：

for col in merged.columns:
    merged[col].values[:] = 1

Answer 2

我已经猜到了我认为您的数据框的外观。

newspaper1 = pd.DataFrame({'author': ['author1', 'author2', 'author3']})
newspaper2 = pd.DataFrame({'author': ['author1', 'author2', 'author4']})
newspaper3 = pd.DataFrame({'author': ['author1', 'author2', 'author5']})
newspaper4 = pd.DataFrame({'author': ['author1', 'author2', 'author6']})

首先，我们将复制数据帧，以免影响原始数据：

newspaper1_temp = newspaper1.copy()
newspaper2_temp = newspaper2.copy()
newspaper3_temp = newspaper3.copy()
newspaper4_temp = newspaper4.copy()

接下来，我们用作者姓名替换每个数据框的索引：

newspaper1_temp.index = newspaper1['author']
newspaper2_temp.index = newspaper2['author']
newspaper3_temp.index = newspaper3['author']
newspaper4_temp.index = newspaper4['author']

然后我们将这些数据帧连接起来（通过我们设置的索引将它们匹配在一起）：

merged = pd.concat([newspaper1_temp, newspaper2_temp, newspaper3_temp, newspaper4_temp], axis =1)
merged.columns = ['newspaper1', 'newspaper2', 'newspaper3', 'newspaper4']

最后我们将NaN替换为0，然后将非零条目（它们中仍将包含作者姓名）替换为1：

merged = merged.fillna(0)
merged[merged != 0] = 1

用for循环填充pandas数据框

2 个答案: