The boundary of the q-numerical range of a reducible matrix

Abstract

In this study, we provide an algorithm for the boundary of the q-numerical range of a reducible matrix. An example is given to show that the q-numerical range cannot be derived from the classical numerical range of matrices.

Keywords:

• Envelope of ellipses
• q-numerical range
• Normal operator
• Reducible matrix

Keywords:

• AMS Subject Classifications: 15A60
• 47A12

Acknowledgement

The first author of this article is partly supported part by NSC Research Project 94-2115-M-031-001.