<p>The paper introduces and considers two new classes of the so-called <i>S</i>-SDD<InlineEquation ID="IEq5"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and <i>S</i>-GSDD<InlineEquation ID="IEq6"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> matrices, where <i>S</i> is a nonempty subset of the set <InlineEquation ID="IEq7"> <EquationSource Format="TEX">\(R_A\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>R</mi> <mi>A</mi> </msub> </math></EquationSource> </InlineEquation> of strictly diagonally dominant rows of <i>A</i>, <InlineEquation ID="IEq8"> <EquationSource Format="TEX">\(k\ge 1\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>k</mi> <mo>≥</mo> <mn>1</mn> </mrow> </math></EquationSource> </InlineEquation>, and <InlineEquation ID="IEq9"> <EquationSource Format="TEX">\(\sigma \in (0,\;1]\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>σ</mi> <mo>∈</mo> <mo stretchy="false">(</mo> <mn>0</mn> <mo>,</mo> <mspace width="0.277778em" /> <mn>1</mn> <mo stretchy="false">]</mo> </mrow> </math></EquationSource> </InlineEquation> is a real parameter. Properties of these matrices and their interrelations with some other matrix classes are considered. In particular, it is shown that <i>S</i>-SDD<InlineEquation ID="IEq10"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and <i>S</i>-GSDD<InlineEquation ID="IEq11"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> matrices are nonsingular <InlineEquation ID="IEq12"> <EquationSource Format="TEX">\({\mathcal {H}}\)</EquationSource> <EquationSource Format="MATHML"><math> <mi mathvariant="script">H</mi> </math></EquationSource> </InlineEquation>-matrices and, moreover, <i>SD</i>-SDD and <i>S</i>-SSDD (Schur SDD) matrices. Based on the latter result, a general parameter-free upper bound for the <InlineEquation ID="IEq13"> <EquationSource Format="TEX">\(l_\infty \)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>l</mi> <mi>∞</mi> </msub> </math></EquationSource> </InlineEquation>-norms of the inverses to <i>S</i>-SDD<InlineEquation ID="IEq14"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and <i>S</i>-GSDD<InlineEquation ID="IEq15"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> matrices is obtained. Also upper bounds for <InlineEquation ID="IEq16"> <EquationSource Format="TEX">\(\Vert A^{-1}\Vert _\infty \)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mrow> <mo stretchy="false">‖</mo> </mrow> <msup> <mi>A</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msup> <msub> <mrow> <mo stretchy="false">‖</mo> </mrow> <mi>∞</mi> </msub> </mrow> </math></EquationSource> </InlineEquation> based on a specific diagonal scaling of <i>S</i>-SDD<InlineEquation ID="IEq17"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and <i>S</i>-SDD<InlineEquation ID="IEq18"> <EquationSource Format="TEX">\(_k(\sigma )\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mmultiscripts> <mrow /> <mi>k</mi> <mrow /> </mmultiscripts> <mrow> <mo stretchy="false">(</mo> <mi>σ</mi> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> matrices <i>A</i>, directly related to their definitions, are provided. Bibliography: 14&#xa0;titles.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

ON S-SDD\(_k(\sigma )\) AND S-GSDD\(_k(\sigma )\) MATRICES

  • L. Yu. Kolotilina

摘要

The paper introduces and considers two new classes of the so-called S-SDD \(_k(\sigma )\) k ( σ ) and S-GSDD \(_k(\sigma )\) k ( σ ) matrices, where S is a nonempty subset of the set \(R_A\) R A of strictly diagonally dominant rows of A, \(k\ge 1\) k 1 , and \(\sigma \in (0,\;1]\) σ ( 0 , 1 ] is a real parameter. Properties of these matrices and their interrelations with some other matrix classes are considered. In particular, it is shown that S-SDD \(_k(\sigma )\) k ( σ ) and S-GSDD \(_k(\sigma )\) k ( σ ) matrices are nonsingular \({\mathcal {H}}\) H -matrices and, moreover, SD-SDD and S-SSDD (Schur SDD) matrices. Based on the latter result, a general parameter-free upper bound for the \(l_\infty \) l -norms of the inverses to S-SDD \(_k(\sigma )\) k ( σ ) and S-GSDD \(_k(\sigma )\) k ( σ ) matrices is obtained. Also upper bounds for \(\Vert A^{-1}\Vert _\infty \) A - 1 based on a specific diagonal scaling of S-SDD \(_k(\sigma )\) k ( σ ) and S-SDD \(_k(\sigma )\) k ( σ ) matrices A, directly related to their definitions, are provided. Bibliography: 14 titles.