Python Pandas - Basic Functionality
Pandas is a powerful data manipulation library in Python, providing essential tools to work with data in both Series and DataFrame formats. These two data structures are crucial for handling and analyzing large datasets.
Understanding the basic functionalities of Pandas, including its attributes and methods, is essential for effectively managing data, these attributes and methods provide valuable insights into your data, making it easier to understand and process. In this tutorial you will learn about the basic attributes and methods in Pandas that are crucial for working with these data structures.
Working with Attributes in Pandas
Attributes in Pandas allow you to access metadata about your Series and DataFrame objects. By using these attributes you can explore and easily understand the data.
Series and DataFrame Attributes
Following are the widely used attribute of the both Series and DataFrame objects −
| Sr.No. | Attribute & Description |
|---|---|
| 1 |
dtype Returns the data type of the elements in the Series or DataFrame. |
| 2 |
index Provides the index (row labels) of the Series or DataFrame. |
| 3 |
values Returns the data in the Series or DataFrame as a NumPy array. |
| 4 |
shape Returns a tuple representing the dimensionality of the DataFrame (rows, columns). |
| 5 |
ndim Returns the number of dimensions of the object. Series is always 1D, and DataFrame is 2D. |
| 6 |
size Gives the total number of elements in the object. |
| 7 |
empty Checks if the object is empty, and returns True if it is. |
| 8 |
columns Provides the column labels of the DataFrame object. |
Example
Let's create a Pandas Series and explore these attributes operation.
import pandas as pd
import numpy as np
# Create a Series with random numbers
s = pd.Series(np.random.randn(4))
# Exploring attributes
print("Data type of Series:", s.dtype)
print("Index of Series:", s.index)
print("Values of Series:", s.values)
print("Shape of Series:", s.shape)
print("Number of dimensions of Series:", s.ndim)
print("Size of Series:", s.size)
print("Is Series empty?:", s.empty)
Its output is as follows −
Data type of Series: float64 Index of Series: RangeIndex(start=0, stop=4, step=1) Values of Series: [-1.02016329 1.40840089 1.36293022 1.33091391] Shape of Series: (4,) Number of dimensions of Series: 1 Size of Series: 4 Is Series empty?: False
Example
Let's look at below example and understand working of these attributes on a DataFrame object.
import pandas as pd
import numpy as np
# Create a DataFrame with random numbers
df = pd.DataFrame(np.random.randn(3, 4), columns=list('ABCD'))
print("DataFrame:")
print(df)
print("Results:")
print("Data types:", df.dtypes)
print("Index:", df.index)
print("Columns:", df.columns)
print("Values:")
print(df.values)
print("Shape:", df.shape)
print("Number of dimensions:", df.ndim)
print("Size:", df.size)
print("Is empty:", df.empty)
On executing the above code you will get the following output −
DataFrame:
A B C D
0 2.161209 -1.671807 -1.020421 -0.287065
1 0.308136 -0.592368 -0.183193 1.354921
2 -0.963498 -1.768054 -0.395023 -2.454112
Results:
Data types:
A float64
B float64
C float64
D float64
dtype: object
Index: RangeIndex(start=0, stop=3, step=1)
Columns: Index(['A', 'B', 'C', 'D'], dtype='object')
Values:
[[ 2.16120893 -1.67180742 -1.02042138 -0.28706468]
[ 0.30813618 -0.59236786 -0.18319262 1.35492058]
[-0.96349817 -1.76805364 -0.3950226 -2.45411245]]
Shape: (3, 4)
Number of dimensions: 2
Size: 12
Is empty: False
Exploring Basic Methods in Pandas
Pandas offers several basic methods in both the data structures, that makes it easy to quickly look at and understand your data. These methods help you get a summary and explore the details without much effort.
Series and DataFrame Methods
| Sr.No. | Method & Description |
|---|---|
| 1 |
head(n) Returns the first n rows of the object. The default value of n is 5. |
| 2 |
tail(n) Returns the last n rows of the object. The default value of n is 5. |
| 3 |
info() Provides a concise summary of a DataFrame, including the index dtype and column dtypes, non-null values, and memory usage. |
| 4 |
describe() Generates descriptive statistics of the DataFrame or Series, such as count, mean, std, min, and max. |
Example
Let us now create a Series and see the working of the Series basic methods.
import pandas as pd
import numpy as np
# Create a Series with random numbers
s = pd.Series(np.random.randn(10))
print("Series:")
print(s)
# Using basic methods
print("First 5 elements of the Series:\n", s.head())
print("\nLast 3 elements of the Series:\n", s.tail(3))
print("\nDescriptive statistics of the Series:\n", s.describe())
Its output is as follows −
Series: 0 -0.295898 1 -0.786081 2 -1.189834 3 -0.410830 4 -0.997866 5 0.084868 6 0.736541 7 0.133949 8 1.023674 9 0.669520 dtype: float64 First 5 elements of the Series: 0 -0.295898 1 -0.786081 2 -1.189834 3 -0.410830 4 -0.997866 dtype: float64 Last 3 elements of the Series: 7 0.133949 8 1.023674 9 0.669520 dtype: float64 Descriptive statistics of the Series: count 10.000000 mean -0.103196 std 0.763254 min -1.189834 25% -0.692268 50% -0.105515 75% 0.535627 max 1.023674 dtype: float64
Example
Now look at below example and understand working of the basic methods on a DataFrame object.
import pandas as pd
import numpy as np
#Create a Dictionary of series
data = {'Name':pd.Series(['Tom','James','Ricky','Vin','Steve','Smith','Jack']),
'Age':pd.Series([25,26,25,23,30,29,23]),
'Rating':pd.Series([4.23,3.24,3.98,2.56,3.20,4.6,3.8])}
#Create a DataFrame
df = pd.DataFrame(data)
print("Our data frame is:\n")
print(df)
# Using basic methods
print("\nFirst 5 rows of the DataFrame:\n", df.head())
print("\nLast 3 rows of the DataFrame:\n", df.tail(3))
print("\nInfo of the DataFrame:")
df.info()
print("\nDescriptive statistics of the DataFrame:\n", df.describe())
On executing the above code you will get the following output −
Our data frame is:
Name Age Rating
0 Tom 25 4.23
1 James 26 3.24
2 Ricky 25 3.98
3 Vin 23 2.56
4 Steve 30 3.20
5 Smith 29 4.60
6 Jack 23 3.80
First 5 rows of the DataFrame:
Name Age Rating
0 Tom 25 4.23
1 James 26 3.24
2 Ricky 25 3.98
3 Vin 23 2.56
4 Steve 30 3.20
Last 3 rows of the DataFrame:
Name Age Rating
4 Steve 30 3.2
5 Smith 29 4.6
6 Jack 23 3.8
Info of the DataFrame:
<class 'pandas.core.frame.DataFrame'>
RangeIndex: 7 entries, 0 to 6
Data columns (total 3 columns):
# Column Non-Null Count Dtype
--- ------ -------------- -----
0 Name 7 non-null object
1 Age 7 non-null int64
2 Rating 7 non-null float64
dtypes: float64(1), int64(1), object(1)
memory usage: 296.0+ bytes
Descriptive statistics of the DataFrame:
Age Rating
count 7.000000 7.000000
mean 25.857143 3.658571
std 2.734262 0.698628
min 23.000000 2.560000
25% 24.000000 3.220000
50% 25.000000 3.800000
75% 27.500000 4.105000
max 30.000000 4.600000