M1: Importing Data Sets

• Each line in a dataset is a row, and commas separate the values.
• To understand the data, you must analyze the attributes for each column of data.
• Python libraries are collections of functions and methods that facilitate various functionalities without writing code from scratch and are categorized into Scientific Computing, Data Visualization, and Machine Learning Algorithms.
• Many data science libraries are interconnected; for instance, Scikit-learn is built on top of NumPy, SciPy, and Matplotlib.
• The data format and the file path are two key factors for reading data with Pandas.
• The read_CSV method in Pandas can read files in CSV format into a Pandas DataFrame.
• Pandas has unique data types like object, float, Int, and datetime.
• Use the dtype method to check each column’s data type; misclassified data types might need manual correction.
• Knowing the correct data types helps apply appropriate Python functions to specific columns.
• Using Statistical Summary with describe() provides count, mean, standard deviation, min, max, and quartile ranges for numerical columns.
• You can also use include='all' as an argument to get summaries for object-type columns.
• The statistical summary helps identify potential issues like outliers needing further attention.
• Using the info() Method gives an overview of the top and bottom 30 rows of the DataFrame, useful for quick visual inspection.
• Some statistical metrics may return "NaN," indicating missing values, and the program can’t calculate statistics for that specific data type.
• Python can connect to databases through specialized code, often written in Jupyter notebooks.
• SQL Application Programming Interfaces (APIs) and Python DB APIs (most often used) facilitate the interaction between Python and the DBMS.
• SQL APIs connect to DBMS with one or more API calls, build SQL statements as a text string, and use API calls to send SQL statements to the DBMS and retrieve results and statuses.
• DB-API, ****Python's standard for interacting with relational databases, ****uses connection objects to establish and manage database connections and cursor objects to run queries and scroll through the results.