An aggregate function is a mathematical function that takes multiple values as input and returns a single value as output. Aggregate functions are commonly used in data analysis and database management systems to summarize, analyze, or compute statistics on a set of data. They are particularly useful when working with large datasets or when performing data aggregation across multiple rows, columns, or groups. When data is aggregated, data rows are replaced with summary statistics such as mean, median, and totals.
- Aggregations: Perform calculations on a group of values, such as sum, mean, median, min, max, or custom functions.
- Value Counts: Count the occurrences of each unique value in a column.
- Head/Tail: Show the first few rows (head) or the last few rows (tail) of a DataFrame.
- NSmallest/NLargest: Get the smallest or largest 'n' values in a column.
- Unique: Get the unique values in a column, often used for understanding the distinct categories or groups in a dataset.
These aggregate functions are helpful for summarizing and analyzing data efficiently. The specific function to use depends on the requirements of your data analysis task and the structure of your dataset.
Updated 5 months ago