MATLAB Release Notes    

Mathematics Upgrade Issues

The issues involved in upgrading from MATLAB 6.1 to MATLAB 6.5, in terms of mathematics features, are discussed below.

Singular Triangular Matrix Division

The result of dividing a singular lower or upper triangular matrix by any other matrix, using either left (\) or right (/) division may change. Previously, for singular square matrices A for which rcond(A) = 0, the result was always a matrix of Infs.

This change is a result of performance improvements described in Mathematics Features.

Example 1.

In MATLAB Version 6.5,

Previously, the result was

Example 2.

In MATLAB 6.5, a zero matrix is treated as a singular triangular matrix.

Previously the result was

  Development Environment Upgrade Issues Programming and Data Types Upgrade Issues