Python Dataframe Adding a description to column
dataframe, pandas, python
Solution
A comment on pandas-dev/pandas#2485 suggests using `_metadata` and `.attrs`. See https://pandas.pydata.org/pandas-docs/stable/development/extending.html#define-original-properties for more information.
One way to do this is to subclass `pandas.DataFrame` and add `_metadata`.
Define `_metadata` for normal properties which will be passed to manipulation results.
import pandas as pd
class SubclassedDataFrame(pd.DataFrame):
# normal properties
_metadata = ['description']
@property
def _constructor(self):
return SubclassedDataFrame
data = {"a": [1, 2, 3], "b": [10, 12, 13]}
df = SubclassedDataFrame(data)
df.description = "About my data"
Setting `_metadata` in the subclass indicates that these properties should be propagated after manipulation. See the example using `.head()` below for a demonstration of the difference between `pd.DataFrame` and this subclass.
data = {"a": [1, 2, 3], "b": [10, 12, 13]}
df = SubclassedDataFrame(data)
df.description = "About my data"
df.head().description # prints 'About my data'
df_orig = pd.DataFrame(data)
df_orig.description = "About my data"
df_orig.head().description # raises AttributeError
Problem
I want to add a description to a column like the source of data from where I collected this. Is such thing is possible? There was a similar question asked about 8 years ago at Adding my own description attribute to a Pandas DataFrame with no answer. My code: ``` df= index colA colB #description from SensorA SensorB # Description row 1 2 3 ```