SbMatrix(3) on Linux
The text 179c061a6e09, as Debian 4.0 (Etch) shipped it.
The SbMatrix class is a 4x4 dimensional representation of a matrix. SbMatrix is used by many other classes in Coin. It provides storage for a 4x4 matrix in row-major mode. Many common geometrical operations which involves matrix calculations are implemented as methods on this class.