如何用iloc和loc替代.ix方法实现时间范围索引切片及代码修复

The .ix indexer was deprecated in Pandas versions starting from 0.20.0 and completely removed in later releases, which is why you're hitting an error. Let's swap it out with the recommended loc or iloc methods, tailored to your data structure.

Quick Look at Your Data Setup #

From your sample, the Date column is set as the index of your returns DataFrame, with columns like BAC Return, MS Return, etc. Since we're filtering by date labels, loc is the most straightforward and reliable choice here.

Updated Code Using loc (Recommended) #

Instead of chaining .ix with column selection, use loc to directly specify both the date range (row labels) and the target column in one clean step:

import seaborn as sns
import pandas as pd

# First, make sure your date index is in datetime format (critical for proper date slicing)
returns.index = pd.to_datetime(returns.index)

# Use loc to grab 2015 data and select the 'MS Return' column
sns.distplot(returns.loc['2015-01-01':'2015-12-31', 'MS Return'], color='green', bins=100)

Why This Works #

• loc['2015-01-01':'2015-12-31'] slices all rows where the index falls within the 2015 calendar year—Pandas handles date range slicing seamlessly when the index is a datetime type.
• Adding , 'MS Return' directly picks the desired column, avoiding potential issues with chained indexing.

Alternative: Using iloc (Position-Based Indexing) #

If you need to use position-based indexing instead, you'll first map the date labels to their integer positions. This is less intuitive for date filtering, but here's how to do it:

# Get the integer positions of your start/end dates
start_pos = returns.index.get_loc('2015-01-01')
end_pos = returns.index.get_loc('2015-12-31')

# Get the position of the 'MS Return' column
ms_col_pos = returns.columns.get_loc('MS Return')

# Use iloc to slice by position (note: iloc excludes the upper bound, so we add +1)
sns.distplot(returns.iloc[start_pos:end_pos+1, ms_col_pos], color='green', bins=100)

内容的提问来源于stack exchange，提问作者Prabhakar Panwar