Introduction to Pandas
Chapter 2: Series
Creating a Series instance
Here is how you create a basic Series instance.
>>> series = pd.Series(data=["UK", "France", "Italy"])
>>> print(series)
0 UK
1 France
2 Italy
dtype: object
You can also pass in the name of the Series to the constructor.
>>> series = pd.Series(data=["UK", "France", "Italy"], name="country")
>>> print(series)
0 UK
1 France
2 Italy
Name: country, dtype: object
As you may have noticed, pandas automatically assigns a sequence starting from 0 as the index (or axis labels) for your data. To customise this, just pass your own index to the constructor!
>>> series = pd.Series(data=["UK", "France", "Italy"],
... index=["a", "b", "c"],
... name="country")
>>> print(series)
a UK
b France
c Italy
Name: country, dtype: object
You can also pass in the dtype keyword argument, which acts just like in NumPy.
Interestingly, you can have duplicate index labels. But this is best avoided. Python will eventually complain anyway when it attempts an operation that does not support duplicate index values. Apparently this is allowed purely for performance reasons.