A note on classes of structured matrices with elliptical type numerical range.
(English).Czechoslovak Mathematical Journal,
vol. 71
(2021),
issue 4,
pp. 1015-1023
Keywords: tridiagonal matrix; antitridiagonal matrix; elliptical disk; numerical range
Summary: We identify new classes of structured matrices whose numerical range is of the elliptical type, that is, an elliptical disk or the convex hull of elliptical disks.
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