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An elementary approach to the matricial Nevanlinna–Pick interpolation criterion

Published online by Cambridge University Press:  20 January 2009

S. C. Power
Affiliation:
Department of MathematicsUniversity of LancasterEngland
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The matricial Nevanlinna–Pick interpolation criterion determines when there is an analytic matrix contraction valued function on the complex unit disc which assumes preassigned n × n matrix values w1,…,wm at preassigned interpolation points z1,…,zm. Taking ∥wi∥ < 1, for i = 1,…,m, the necessary and sufficient condition is the positivity of the nm × nm matricial Pick matrix,

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1989

References

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