Appendix I — Mapping to Axler and to Boyd & Vandenberghe
This appendix maps our 40 chapters to two further classics that this book is in conversation with, each representing a different philosophy:
- Sheldon Axler, Linear Algebra Done Right (Springer; the 4th edition is freely readable online). The rigorous, proof-first counterpart. Axler develops the entire subject through linear maps on abstract vector spaces and famously delays determinants to the very last chapter, deriving eigenvalue theory without them.
- Stephen Boyd & Lieven Vandenberghe, Introduction to Applied Linear Algebra:
Vectors, Matrices, and Least Squares (Cambridge; free PDF at
vmls-book.stanford.edu, hence "VMLS"). The applied counterpart — organized around vectors, matrices, and least squares, with worked examples from data fitting, control, and machine learning, and almost no abstract proof.
Because these books are organized so differently from ours, the mappings are
topic-level, and many are approximate — flagged [verify]. Axler's section structure
in particular was reorganized between the 3rd and 4th editions; confirm against your copy.
I.1 The two ordering philosophies to keep in mind
Before the table, the two structural facts that drive most of the mismatches:
- Axler is determinant-last and proof-first. He treats eigenvalues, the spectral theorem, and operator theory before determinants, which appear only in his final chapter (with the trace). This is the opposite of both this book (determinants in Part II) and Strang (determinants in the middle). An Axler-aligned reader should expect our Chapter 11 to have no early counterpart in Axler, and our eigenvalue chapters (23–28) to be where Axler's core lives.
- Boyd is applied and least-squares-centric. VMLS has three parts — Vectors (chs. 1–5), Matrices (chs. 6–11), and Least Squares (chs. 12–19) — and deliberately omits determinants, eigenvalues, the SVD, and abstract vector spaces to stay focused on what a data/engineering practitioner uses most. So several of our later chapters have no Boyd counterpart at all, marked "—".
I.2 Chapter-by-chapter correspondence
| This book (chapter · topic) | Axler, LADR (topic) | Boyd–Vandenberghe (VMLS topic) |
|---|---|---|
| 1. What Is Linear Algebra? | Preface / Ch. 1 intro [verify] |
Ch. 1 Vectors (intro) |
| 2. Vectors | 1A $\mathbb{R}^n$, $\mathbb{C}^n$ | Ch. 1 Vectors; Ch. 3 norm/distance |
| 3. Systems of Linear Equations | (not central; via linear maps) [verify] |
Ch. 8 Linear equations; Ch. 11 solving $A\mathbf{x}=\mathbf{b}$ |
| 4. Gaussian Elimination & Row Reduction | (not emphasized) [verify] |
Ch. 11 (matrix inverses, solving) [verify] |
| 5. Vector Spaces | 1B–1C Definition and subspaces | (concrete only; no axiomatic treatment) — |
| 6. Subspaces, Span, Linear Independence | 2A Span and independence; 2B bases | Ch. 5 Linear independence; Ch. 5 basis |
| 7. Matrices as Functions | 3A–3B Linear maps; matrix of a map | Ch. 6 Matrices; Ch. 10 matrix-vector product |
| 8. Matrix Operations | 3C Matrix multiplication; 3D | Ch. 6, Ch. 10 (products, transpose) |
| 9. The Inverse Matrix | 3D Invertibility, isomorphisms | Ch. 11 Matrix inverses |
| 10. LU & PLU Decomposition | (not covered) [verify] |
Ch. 11 (factor-solve perspective) [verify] |
| 11. The Determinant | Ch. 10 (last chapter!) — Trace and determinant | — (omitted in VMLS) |
| 12. Application: Computer Graphics | (not covered) | (not covered) — |
| 13. Column Space & Null Space | 3B Range and null space (kernel) | Ch. 5; Ch. 8 (range/nullspace via least squares) [verify] |
| 14. Row Space, Left Null Space, Rank–Nullity | 3B Fundamental theorem of linear maps (rank–nullity) | Ch. 10 (rank); not the four-subspace framing [verify] |
| 15. Dimension, Basis, Coordinates | 2C Dimension | Ch. 5 (basis, dimension) |
| 16. Change of Basis | 3F Change of basis; 10A [verify] |
(light) [verify] |
| 17. Application: Linear Regression | (not an applications book) | Ch. 12–13 Least squares & data fitting (core VMLS) |
| 18. Dot Products, Norms, Angles | 6A Inner products and norms | Ch. 3 Norm, distance, angle; Ch. 4 |
| 19. Orthogonal Projection | 6B Orthonormal bases; projections | Ch. 12 (least squares = projection) |
| 20. Gram–Schmidt & QR | 6B Gram–Schmidt | Ch. 5 / Ch. 10 QR factorization; Ch. 12 |
| 21. Orthogonal Matrices & Rotations | 7 (isometries); 6 orthonormal | Ch. 7 Matrix examples (rotations) [verify] |
| 22. Application: Fourier Series | 6B (orthonormal expansions) [verify] |
(not covered) — |
| 23. Eigenvalues & Eigenvectors | 5A–5B Eigenvalues, invariant subspaces | — (omitted in VMLS) |
| 24. The Characteristic Polynomial | 5 / 8 (Axler develops eigenvalues without det first) | — |
| 25. Diagonalization | 5C Eigenspaces and diagonal matrices | — |
| 26. Complex Eigenvalues | 8 Operators on complex/real vector spaces | — |
| 27. The Spectral Theorem | 7A–7B The spectral theorem (a high point of Axler) | — |
| 28. Positive Definite & Quadratic Forms | 7C Positive operators; isometries | (touched via least squares / Gram matrix) [verify] |
| 29. Application: PageRank | (not covered) | (not covered) — |
| 30. Singular Value Decomposition | 7E–7F The SVD (added prominence in 4th ed.) [verify] |
— (omitted in VMLS) |
| 31. SVD Applications | (briefly, via SVD section) [verify] |
— |
| 32. Principal Component Analysis | (not covered) | (PCA-adjacent via least squares) [verify] |
| 33. Application: Machine Learning | (not an applications book) | Ch. 13–14 (classification, fitting) [verify] |
| 34. Inner Product Spaces | Ch. 6 (the core of Axler's geometry) | Ch. 3 (concrete inner products only) |
| 35. Linear Transformations & Abstract Vector Spaces | Ch. 3 (the spine of the whole book) | (concrete maps only) — |
| 36. Jordan Normal Form | 8D Generalized eigenvectors; nilpotents (Axler's route to Jordan-type results) [verify] |
— |
| 37. Matrix Exponential & Systems of ODEs | (not covered) [verify] |
(not covered) — |
| 38. Numerical Linear Algebra | (not covered; Axler is non-numerical) | Ch. 11–12 (conditioning touched lightly) [verify] |
| 39. Capstone | — | VMLS exercises / applications |
| 40. Where Linear Algebra Goes Next | Epilogue [verify] |
Appendix / further directions [verify] |
I.3 How to use each book alongside this one
If you are a math major reading Axler in parallel: treat our geometry-first chapters as the intuition layer beneath Axler's proofs. Our Chapters 5, 7, and 35 (vector spaces, matrices-as-maps, abstract transformations) are the on-ramps to his Chapters 1–3; our Chapters 23–28 line up with his eigenvalue and spectral-theorem core (Axler's Chapters 5–7); and his determinant-last philosophy means you should read our Chapter 11 as a geometric account he deliberately postpones. Axler's payoff — that you can do eigenvalue theory without determinants — is visible in how little our eigenvalue chapters actually lean on Chapter 11.
If you are a CS/data-science reader keeping Boyd open for applications: VMLS is the best companion for the applied chapters — Chapter 17 (regression), Chapters 18–20 (orthogonality and least squares), and Chapter 33 (machine learning) map directly onto its least-squares core (VMLS Parts II–III). But VMLS deliberately stops short of determinants, eigenvalues, the SVD, and abstract spaces — so for Chapters 11 and 23–36 you will want Strang (Appendix H) or this book alone. Think of Boyd as the deep, practical treatment of half this book — the half a practitioner uses daily — done with exceptional clarity.
A note on honesty in this table. Where a cell says "not covered" or "—," that is a real
scope difference, not an oversight: Axler omits applications and numerics by design, and
Boyd omits eigenvalues, the SVD, determinants, and abstraction by design. The [verify]
flags mark places where the section-level fit depends on the edition or where a topic is
present but not in a cleanly corresponding unit. Trust the topic names over the structure.