Resumen: In this paper, an accurate method to construct the bidiagonal factorization of Gram (mass) matrices of Bernstein bases of positive and negative degree is obtained and used to compute with high relative accuracy their eigenvalues, singular values and inverses. Numerical examples are included. Idioma: Inglés DOI: 10.1007/s11075-022-01284-0 Año: 2022 Publicado en: NUMERICAL ALGORITHMS 91 (2022), 841–859 ISSN: 1017-1398 Factor impacto JCR: 2.1 (2022) Categ. JCR: MATHEMATICS, APPLIED rank: 59 / 267 = 0.221 (2022) - Q1 - T1 Factor impacto CITESCORE: 4.4 - Mathematics (Q1)