v2010.10.26 - Convex Optimization
v2010.10.26 - Convex Optimization v2010.10.26 - Convex Optimization
544 CHAPTER 6. CONE OF DISTANCE MATRICESWhen N = 1, the EDM cone and its dual in ambient S h each comprisethe origin in isomorphic R 0 ; thus, selfdual in this dimension. (confer (104))When N = 2, the EDM cone is the nonnegative real line in isomorphic R .(Figure 142) EDM 2∗ in S 2 h is identical, thus selfdual in this dimension.This [ result]is in agreement [ with ](1294), verified directly: for all κ∈ R ,11z = κ and δ(zz−1T ) = κ 2 ⇒ d ∗ 12 ≥ 0.1The first case adverse to selfdualness N = 3 may be deduced fromFigure 138; the EDM cone is a circular cone in isomorphic R 3 correspondingto no rotation of Lorentz cone (178) (the selfdual circular cone). Figure 151illustrates the EDM cone and its dual in ambient S 3 h ; no longer selfdual.6.9 Theorem of the alternativeIn2.13.2.1.1 we showed how alternative systems of generalized inequalitycan be derived from closed convex cones and their duals. This section is,therefore, a fitting postscript to the discussion of the dual EDM cone.6.9.0.0.1 Theorem. EDM alternative. [163,1]Given D ∈ S N hD ∈ EDM Nor in the alternative{1 T z = 1∃ z such thatDz = 0(1297)In words, either N(D) intersects hyperplane {z | 1 T z =1} or D is an EDM;the alternatives are incompatible.⋄When D is an EDM [259,2]N(D) ⊂ N(1 T ) = {z | 1 T z = 0} (1298)Because [163,2] (E.0.1)thenDD † 1 = 11 T D † D = 1 T (1299)R(1) ⊂ R(D) (1300)
6.10. POSTSCRIPT 5456.10 PostscriptWe provided an equality (1268) relating the convex cone of Euclidean distancematrices to the convex cone of positive semidefinite matrices. Projection ona positive semidefinite cone, constrained by an upper bound on rank, is easyand well known; [129] simply, a matter of truncating a list of eigenvalues.Projection on a positive semidefinite cone with such a rank constraint is, infact, a convex optimization problem. (7.1.4)In the past, it was difficult to project on the EDM cone under aconstraint on rank or affine dimension. A surrogate method was to invokethe Schoenberg criterion (910) and then project on a positive semidefinitecone under a rank constraint bounding affine dimension from above. But asolution acquired that way is necessarily suboptimal.In7.3.3 we present a method for projecting directly on the EDM coneunder a constraint on rank or affine dimension.
- Page 493 and 494: 5.14. FIFTH PROPERTY OF EUCLIDEAN M
- Page 495 and 496: 5.14. FIFTH PROPERTY OF EUCLIDEAN M
- Page 497 and 498: Chapter 6Cone of distance matricesF
- Page 499 and 500: 6.1. DEFINING EDM CONE 4996.1 Defin
- Page 501 and 502: 6.2. POLYHEDRAL BOUNDS 501This cone
- Page 503 and 504: 6.4. EDM DEFINITION IN 11 T 503That
- Page 505 and 506: 6.4. EDM DEFINITION IN 11 T 505N(1
- Page 507 and 508: 6.4. EDM DEFINITION IN 11 T 507Then
- Page 509 and 510: 6.4. EDM DEFINITION IN 11 T 5096.4.
- Page 511 and 512: 6.5. CORRESPONDENCE TO PSD CONE S N
- Page 513 and 514: 6.5. CORRESPONDENCE TO PSD CONE S N
- Page 515 and 516: 6.5. CORRESPONDENCE TO PSD CONE S N
- Page 517 and 518: 6.6. VECTORIZATION & PROJECTION INT
- Page 519 and 520: 6.6. VECTORIZATION & PROJECTION INT
- Page 521 and 522: 6.6. VECTORIZATION & PROJECTION INT
- Page 523 and 524: 6.7. A GEOMETRY OF COMPLETION 523(b
- Page 525 and 526: 6.7. A GEOMETRY OF COMPLETION 525[3
- Page 527 and 528: 6.7. A GEOMETRY OF COMPLETION 527wh
- Page 529 and 530: 6.8. DUAL EDM CONE 529to the geomet
- Page 531 and 532: 6.8. DUAL EDM CONE 531Proof. First,
- Page 533 and 534: 6.8. DUAL EDM CONE 533EDM 2 = S 2 h
- Page 535 and 536: 6.8. DUAL EDM CONE 535therefore the
- Page 537 and 538: 6.8. DUAL EDM CONE 537Elegance of t
- Page 539 and 540: 6.8. DUAL EDM CONE 5396.8.1.5 Affin
- Page 541 and 542: 6.8. DUAL EDM CONE 5416.8.1.7 Schoe
- Page 543: 6.8. DUAL EDM CONE 5430dvec rel ∂
- Page 547 and 548: Chapter 7Proximity problemsIn the
- Page 549 and 550: 549project on the subspace, then pr
- Page 551 and 552: 551HS N h0EDM NK = S N h ∩ R N×N
- Page 553 and 554: 5537.0.3 Problem approachProblems t
- Page 555 and 556: 7.1. FIRST PREVALENT PROBLEM: 555fi
- Page 557 and 558: 7.1. FIRST PREVALENT PROBLEM: 5577.
- Page 559 and 560: 7.1. FIRST PREVALENT PROBLEM: 559di
- Page 561 and 562: 7.1. FIRST PREVALENT PROBLEM: 5617.
- Page 563 and 564: 7.1. FIRST PREVALENT PROBLEM: 563wh
- Page 565 and 566: 7.1. FIRST PREVALENT PROBLEM: 565Th
- Page 567 and 568: 7.2. SECOND PREVALENT PROBLEM: 567O
- Page 569 and 570: 7.2. SECOND PREVALENT PROBLEM: 569S
- Page 571 and 572: 7.2. SECOND PREVALENT PROBLEM: 571r
- Page 573 and 574: 7.2. SECOND PREVALENT PROBLEM: 573w
- Page 575 and 576: 7.2. SECOND PREVALENT PROBLEM: 5757
- Page 577 and 578: 7.2. SECOND PREVALENT PROBLEM: 577a
- Page 579 and 580: 7.3. THIRD PREVALENT PROBLEM: 579is
- Page 581 and 582: 7.3. THIRD PREVALENT PROBLEM: 581We
- Page 583 and 584: 7.3. THIRD PREVALENT PROBLEM: 583su
- Page 585 and 586: 7.3. THIRD PREVALENT PROBLEM: 585Gi
- Page 587 and 588: 7.3. THIRD PREVALENT PROBLEM: 587Op
- Page 589 and 590: 7.4. CONCLUSION 589filtering, multi
- Page 591 and 592: Appendix ALinear algebraA.1 Main-di
- Page 593 and 594: A.1. MAIN-DIAGONAL δ OPERATOR, λ
6.10. POSTSCRIPT 5456.10 PostscriptWe provided an equality (1268) relating the convex cone of Euclidean distancematrices to the convex cone of positive semidefinite matrices. Projection ona positive semidefinite cone, constrained by an upper bound on rank, is easyand well known; [129] simply, a matter of truncating a list of eigenvalues.Projection on a positive semidefinite cone with such a rank constraint is, infact, a convex optimization problem. (7.1.4)In the past, it was difficult to project on the EDM cone under aconstraint on rank or affine dimension. A surrogate method was to invokethe Schoenberg criterion (910) and then project on a positive semidefinitecone under a rank constraint bounding affine dimension from above. But asolution acquired that way is necessarily suboptimal.In7.3.3 we present a method for projecting directly on the EDM coneunder a constraint on rank or affine dimension.