# Unimodular matrix

From Encyclopedia of Mathematics

A square matrix with determinant . Sometimes when considering matrices over a commutative ring one understands by a unimodular matrix an invertible matrix.

#### Comments

Often also a unimodular matrix is meant to have determinant . The unimodular matrices, in any of the meanings, form a group under multiplication. Cf. also Unimodular transformation.

**How to Cite This Entry:**

Unimodular matrix. O.A. Ivanova (originator),

*Encyclopedia of Mathematics.*URL: http://www.encyclopediaofmath.org/index.php?title=Unimodular_matrix&oldid=15584

This text originally appeared in Encyclopedia of Mathematics - ISBN 1402006098