Pandas offers two primary data structures: `Series` and `DataFrame`. The `Series` is the simpler of the two, resembling a **one-dimensional** array or a list. You can create a `Series` object using the `pd.Series()` constructor by passing a **list** as its argument.

import pandas as pd
numbers = [17, 43, 74, 20]
series = pd.Series(numbers)

print(series)

In this example, we use the `pd.Series()` constructor to create a `Series` object containing a **list of numbers**.

import unittest
import importlib
import pandas as pd


# Helper function to dynamically generate test names and assertions
def _dynamic_test(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
        test_case.assertTrue(True, success_message)
    else:
        test_case._testMethodName = failure_message
        test_case.fail(failure_message)


class TestUserCode(unittest.TestCase):

    def test_numbers_series_is_declared(self):
        import user_code
        _dynamic_test(
            self,
            hasattr(user_code, 'numbers_series'),
            "The `numbers_series` variable is declared.",
            "Expected `numbers_series` to be declared."
        )

    def test_states_series_is_declared(self):
        import user_code
        _dynamic_test(
            self,
            hasattr(user_code, 'states_series'),
            "The `states_series` variable is declared.",
            "Expected `states_series` to be declared."
        )

    def test_numbers_series_is_pandas_series(self):
        import user_code

        try:
            actual_value = user_code.numbers_series
            condition = isinstance(actual_value, pd.Series)
            failure_message = f"Expected `numbers_series` to be a `Series`, but got `{type(user_code.numbers_series).__name__}`."
        except AttributeError:
            condition = False
            failure_message = "The `numbers_series` variable is not declared."

        _dynamic_test(
            self,
            condition,
            "The variable `numbers_series` is a `Series`.",
            failure_message
        )

    def test_states_series_is_pandas_series(self):
        import user_code

        try:
            actual_value = user_code.states_series
            condition = isinstance(actual_value, pd.Series)
            failure_message = f"Expected `states_series` to be a `Series`, but got `{type(user_code.states_series).__name__}`."
        except AttributeError:
            condition = False
            failure_message = "The `states_series` variable is not declared."

        _dynamic_test(
            self,
            condition,
            "The variable `states_series` is a `Series`.",
            failure_message
        )

    def test_numbers_series_has_correct_values(self):
        import user_code
        expected_value = pd.Series([2, 4, 8, 16])

        variable = 'numbers_series'
        actual_value = getattr(user_code, variable, None)
        if actual_value is None:
            condition = False
            failure_message = f"The `{variable}` variable is not declared."
        elif isinstance(actual_value, pd.Series):
            condition = actual_value.equals(expected_value)
            if actual_value.empty:
                failure_message = f"`{variable}` is empty."
            else:
                failure_message = f"Expected `{variable}` to contain `{expected_value.values}`, but got `{actual_value.values}`."
        else:
            condition = False
            failure_message = f"`{variable}` is not a `Series`."

        _dynamic_test(
            self,
            condition,
            f"`{variable}` contains the correct values.",
            failure_message
        )

    def test_states_series_has_correct_values(self):
        import user_code
        expected_value = pd.Series(["New York", "California", "Chicago", "Alaska"])

        variable = 'states_series'
        actual_value = getattr(user_code, variable, None)
        if actual_value is None:
            condition = False
            failure_message = f"The `{variable}` variable is not declared."
        elif isinstance(actual_value, pd.Series):
            condition = actual_value.equals(expected_value)
            if actual_value.empty:
                failure_message = f"`{variable}` is empty."
            else:
                failure_message = f"Expected `{variable}` to contain `{expected_value.values}`, but got `{actual_value.values}`."
        else:
            condition = False
            failure_message = f"`{variable}` is not a `Series`."

        _dynamic_test(
            self,
            condition,
            f"`{variable}` contains the correct values.",
            failure_message
        )


if __name__ == '__main__':
    unittest.main()

test_main.py

Pandas is an extremely user-friendly library for data analysis. It's also designed to handle large datasets, using data structures like DataFrame and Series. This makes it an invaluable tool for Data Science. In this guide, you'll get acquainted with a range of statistical functions, including how to find correlations, modes, medians, and maximum and minimum values within a dataset. You'll also learn how to handle missing values and manipulate specific values, as well as how to remove them.

In this section, we'll explore the fundamentals of Series and DataFrame structures. You'll also learn about the distinctions between these two types of structures.

Data can be sourced in various formats, such as CSV, JSON, SQL, HTML, and more. With Pandas, you're not limited to a single format — you can work with data across a multitude of file types. In this chapter, we'll specifically focus on the CSV and TXT formats.

Here, you'll learn how to process raw data by removing extraneous information and managing null values in a dataset.

Pandas First Steps

Series

Solution

Series

Solution