Python iloc 给出“IndexError：单个位置索引器越界”
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iloc giving 'IndexError: single positional indexer is out-of-bounds'
提问by Taylrl
I am trying to encode some information to read into a Machine Learning model using the following
我正在尝试使用以下方法对一些信息进行编码以读入机器学习模型
import numpy as np
import pandas as pd
import matplotlib.pyplot as py
Dataset = pd.read_csv('filename.csv', sep = ',')
X = Dataset.iloc[:,:-1].values
Y = Dataset.iloc[:,18].values
from sklearn.preprocessing import LabelEncoder, OneHotEncoder
labelencoder_X = LabelEncoder()
X[:, 0] = labelencoder_X.fit_transform(X[:, 0])
onehotencoder = OneHotEncoder(categorical_features = [0])
X = onehotencoder.fit_transform(X).toarray()
however I am getting an error that reads
但是我收到一个错误消息
IndexError: single positional indexer is out-of-bounds
回答by slonopotam
This error is caused by:
此错误是由以下原因引起的：
Y = Dataset.iloc[:,18].values
Indexing is out of bounds here most probably because there are less than 19 columns in your Dataset, so column 18 does not exist. The following code you provided doesn't use Y at all, so you can just comment out this line for now.
此处的索引超出范围很可能是因为您的数据集中的列少于 19 列，因此第 18 列不存在。您提供的以下代码根本不使用 Y，因此您现在可以注释掉这一行。
回答by Nicolas Gervais
This happens when you index a row/column with a number that is larger than the dimensions of your dataframe. For instance, getting the eleventh column when you have only three.
当您索引行/列的数字大于dataframe. 例如，当您只有三列时获得第十一列。
import pandas as pd
df = pd.DataFrame({'Name': ['Mark', 'Laura', 'Adam', 'Roger', 'Anna'],
'City': ['Lisbon', 'Montreal', 'Lisbon', 'Berlin', 'Glasgow'],
'Car': ['Tesla', 'Audi', 'Porsche', 'Ford', 'Honda']})
You have 5 rows and three columns:
您有 5 行和3 列：
Name City Car
0 Mark Lisbon Tesla
1 Laura Montreal Audi
2 Adam Lisbon Porsche
3 Roger Berlin Ford
4 Anna Glasgow Honda
Let's try to index the eleventh column(it doesn't exist):
让我们尝试索引第十一列（它不存在）：
df.iloc[:, 10] # there is obviously no 11th column
IndexError: single positional indexer is out-of-bounds
IndexError：单个位置索引器越界
If you are a beginner with Python, remember that df.iloc[:, 10]would refer to the eleventh column.
如果您是 Python 初学者，请记住df.iloc[:, 10]将参考第十一栏。
回答by Qalb E Abbas
Lenghten your CSV file: add more rows and columns. It was not working for me when file was small. I lenghtened and now it worked.
延长 CSV 文件：添加更多行和列。当文件很小时，它对我不起作用。我加长了，现在它起作用了。
