# 10.6. Glossary¶

## 10.6.1. Definitions¶

**Adjacency Matrix:** is a square matrix that is used to represent a finite graph. The elements of the matrix indicate whether pairs of vertices are adjacent or not.

**Chord Diagram:** is a visual representation method to display the inter-relationships between data in a matrix.

**Co-occurrence matrix:** is a matrix defined over an image to be the distribution of co-occurring pixel values at a given offset.

**Lower Triangular Matrix:** is a square matrix in which all the entries above the main diagonal are zero.

**Market Basket Analysis:** is a technique used to find associations between different items. It helps retailers uncover the relationship between things that consumers frequently buy together

**Matrix:** is a rectangular arrangement of numbers, symbols, or expressions in rows and columns

**Sparse Matrix:** is a matrix that contains mostly zeros. If the matrix has a lot of non-zero values, then the matrix would be considered dense.

## 10.6.2. Keywords¶

`get_group`

allows us to get a data frame containing only the items in one particular order

`idxmax`

allows us to get a series that tells us the row(s) with the highest value(s) from each column in the DataFrame.