When is a matrix a sum of idempotents?

1990/03/01 by Robert E. Hartwig, Mohan S. Putcha · 4 citations
Computer Science · Mathematics · Engineering · #Matrix Theory and Algorithms #Advanced Topics in Algebra #graph theory and CDMA systems

paper · doi:10.1080/03081089008817984

Abstract

It is shown that a matrix A, ovei a field of characteristic zero, is a sum of idempotents. exactly when the trace of A is an integer at least as large as rank(A).

Citations

• When is a matrix a difference of two idempotents

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