Pandas Data Structure - Series
A Pandas Series is similar to a column in a table, akin to a one-dimensional array, capable of holding any data type.
A Series consists of an index and columns, with the function as follows:
pandas.Series(data, index, dtype, name, copy)
Parameter descriptions:
- data: A set of data (ndarray type).
- index: Data index labels; if not specified, default to starting from 0.
- dtype: Data type; defaults to auto-detection.
- name: Sets the name.
- copy: Copies the data; defaults to False.
Creating a simple Series instance:
Example
import pandas as pd
a = [1, 2, 3]
myvar = pd.Series(a)
print(myvar)
Output is as follows:
From the figure, if no index is specified, the index values start from 0. We can retrieve data based on the index value:
Example
import pandas as pd
a = [1, 2, 3]
myvar = pd.Series(a)
print(myvar[1])
Output is as follows:
2
We can specify index values, as shown in the following example:
Example
import pandas as pd
a = ["Google", "tutorialpro", "Wiki"]
myvar = pd.Series(a, index=["x", "y", "z"])
print(myvar)
Output is as follows:
Retrieving data by index value:
Example
import pandas as pd
a = ["Google", "tutorialpro", "Wiki"]
myvar = pd.Series(a, index=["x", "y", "z"])
print(myvar["y"])
Output is as follows:
tutorialpro
We can also create a Series using a key/value object, similar to a dictionary:
Example
import pandas as pd
sites = {1: "Google", 2: "tutorialpro", 3: "Wiki"}
myvar = pd.Series(sites)
print(myvar)
Output is as follows:
From the figure, the dictionary's keys become the index values.
If we only need a portion of the dictionary's data, we can specify the required data's index, as shown in the following example:
Example
import pandas as pd
sites = {1: "Google", 2: "tutorialpro", 3: "Wiki"}
myvar = pd.Series(sites, index=[1, 2])
print(myvar)
Output is as follows:
Setting the Series name parameter:
Example
import pandas as pd
sites = {1: "Google", 2: "tutorialpro", 3: "Wiki"}
myvar = pd.Series(sites, index=[1, 2], name="tutorialpro-Series-TEST")
print(myvar)
Output is as follows: