mbend: an R package for bending non-positive-definite symmetric matrices to positive-definite
نویسندگان
چکیده
منابع مشابه
DDtBe for Band Symmetric Positive Definite Matrices
We present a new parallel factorization for band symmetric positive definite (s.p.d) matrices and show some of its applications. Let A be a band s.p.d matrix of order n and half bandwidth m. We show how to factor A as A =DDt Be using approximately 4nm2 jp parallel operations where p =21: is the number of processors. Having this factorization, we improve the time to solve Ax = b by a factor of m...
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Metric learning has been shown to be highly effective to improve the performance of nearest neighbor classification. In this paper, we address the problem of metric learning for symmetric positive definite (SPD) matrices such as covariance matrices, which arise in many real-world applications. Naively using standard Mahalanobis metric learning methods under the Euclidean geometry for SPD matric...
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ژورنال
عنوان ژورنال: BMC Genetics
سال: 2020
ISSN: 1471-2156
DOI: 10.1186/s12863-020-00881-z