Python 如何使用 Pandas 向新列添加增量数字
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How to Add Incremental Numbers to a New Column Using Pandas
提问by MEhsan
I have this simplified dataframe:
我有这个简化的数据框：
ID Fruit
F1 Apple
F2 Orange
F3 Banana
I want to add in the begining of the dataframe a new column df['New_ID']which has the number 880that increments by one in each row.
我想在数据帧的开头添加一个新列df['New_ID']，该列的数字880在每行中递增 1。
The output should be simply like:
输出应该简单地像：
New_ID ID Fruit
880 F1 Apple
881 F2 Orange
882 F3 Banana
I tried the following:
我尝试了以下方法：
df['New_ID'] = ["880"] # but I want to do this without assigning it the list of numbers literally
Any idea how to solve this?
知道如何解决这个问题吗？
Thanks!
谢谢！
采纳答案by Kartik
Here:
这里：
df = df.reset_index()
df.columns[0] = 'New_ID'
df['New_ID'] = df.index + 880
回答by piRSquared
df.insert(0, 'New_ID', range(880, 880 + len(df)))
df
回答by naman
You can also simply set your pandas column as list of id values with length same as of dataframe.
您也可以简单地将您的 Pandas 列设置为长度与数据框相同的 id 值列表。
df['New_ID'] = range(880, 880+len(df))
Reference docs : https://pandas.pydata.org/pandas-docs/stable/missing_data.html
参考文档：https: //pandas.pydata.org/pandas-docs/stable/missing_data.html
回答by Alexander
df = df.assign(New_ID=[880 + i for i in xrange(len(df))])[['New_ID'] + df.columns.tolist()]
>>> df
New_ID ID Fruit
0 880 F1 Apple
1 881 F2 Orange
2 882 F3 Banana
回答by Bahati Felix
import numpy as np
df['New_ID']=np.arange(880,880+len(df.Fruit))
df=df.reindex(columns=['New_ID','ID','Fruit'])
