Update title and attribution for Devito edition

- Change subtitle from "A Modern Software Approach" to "A Devito Approach"
- Add "About This Adaptation" section to preface with CC BY 4.0 attribution
- Fix license from CC BY-NC 4.0 to CC BY 4.0 (matching original work)
- Add adapter credit (Gerard J. Gorman, Imperial College London)
- Create LICENSE file with full attribution requirements
- Add license badge and DOI link to README and index

Author: ggorman

LICENSE

@@ -0,0 +1,28 @@
+# License
+
+## This Adapted Work
+
+"Finite Difference Computing with PDEs: A Devito Approach" is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0).
+
+https://creativecommons.org/licenses/by/4.0/
+
+## Original Work
+
+This work is adapted from:
+
+**Finite Difference Computing with PDEs: A Modern Software Approach**
+by Hans Petter Langtangen and Svein Linge
+
+- Publisher: Springer International Publishing (2017)
+- DOI: https://doi.org/10.1007/978-3-319-55456-3
+- License: CC BY 4.0
+- Source: https://github.com/hplgit/fdm-book
+
+## Attribution
+
+When reusing this work, please credit:
+1. Original authors: Hans Petter Langtangen and Svein Linge
+2. Adapter: Gerard J. Gorman
+3. Link to original DOI
+4. Link to CC BY 4.0 license
+5. Note that changes were made

README.md

@@ -66,9 +66,9 @@ Install [Quarto](https://quarto.org/docs/get-started/):
 # macOS
 brew install quarto
 
-# Ubuntu/Debian
-wget https://github.com/quarto-dev/quarto-cli/releases/latest/download/quarto-linux-amd64.deb
-sudo dpkg -i quarto-linux-amd64.deb
+# Ubuntu/Debian - see https://quarto.org/docs/get-started/ for current version
+# Download the .deb from https://github.com/quarto-dev/quarto-cli/releases/latest
+sudo dpkg -i quarto-*.deb
 ```
 
 ### LaTeX (for PDF output)
@@ -158,16 +158,28 @@ Pre-commit hooks enforce:
 
 ## License
 
-Content: [CC BY-NC 4.0](https://creativecommons.org/licenses/by-nc/4.0/)
+[![CC BY 4.0](https://img.shields.io/badge/License-CC%20BY%204.0-lightgrey.svg)](https://creativecommons.org/licenses/by/4.0/)
+
+This work is adapted from:
+
+> Langtangen, H.P., Linge, S. (2017). *Finite Difference Computing with PDEs: A Modern Software Approach*. Springer, Cham. [DOI: 10.1007/978-3-319-55456-3](https://doi.org/10.1007/978-3-319-55456-3)
+
+Licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).
 
 ## Authors
 
+**Original Authors:**
+
 - Hans Petter Langtangen (1962-2016)
 - Svein Linge
 
+**Adapted by:**
+
+- Gerard J. Gorman, Imperial College London
+
 ## Links
 
 - [Devito Project](https://www.devitoproject.org/)
-- [Devito Documentation](https://www.devitoproject.org/devito/index.html)
+- [Devito API Reference](https://www.devitoproject.org/api/)
 - [Devito GitHub](https://github.com/devitocodes/devito)
 - [Original Book (PDF)](https://hplgit.github.io/fdm-book/doc/pub/book/pdf/fdm-book-4print.pdf)

_quarto.yml

@@ -4,7 +4,7 @@ project:
 
 book:
   title: "Finite Difference Computing with PDEs"
-  subtitle: "A Modern Software Approach"
+  subtitle: "A Devito Approach"
   author:
     - name: Hans Petter Langtangen
     - name: Svein Linge

chapters/preface/preface.qmd

@@ -1,3 +1,47 @@
+## About This Adaptation {.unnumbered}
+
+This book is an adaptation of *Finite Difference Computing with PDEs: A Modern Software Approach* by Hans Petter Langtangen and Svein Linge, originally published by Springer in 2017 under a [Creative Commons Attribution 4.0 International License (CC BY 4.0)](https://creativecommons.org/licenses/by/4.0/).
+
+**Original Work:**
+
+> Langtangen, H.P., Linge, S. (2017). *Finite Difference Computing with PDEs: A Modern Software Approach*. Texts in Computational Science and Engineering, vol 16. Springer, Cham. [https://doi.org/10.1007/978-3-319-55456-3](https://doi.org/10.1007/978-3-319-55456-3)
+
+### What Has Changed
+
+This edition has been substantially adapted to feature [Devito](https://www.devitoproject.org/), a domain-specific language for symbolic PDE specification and automatic code generation.
+
+**New Content:**
+
+- Introduction to Devito chapter covering Grid, Function, TimeFunction, and Operator
+- Devito solver implementations for wave, diffusion, advection, and nonlinear equations
+- Comprehensive exercises using Devito
+- Test suite with verification of all numerical methods
+
+**Technical Updates:**
+
+- Conversion from DocOnce to [Quarto](https://quarto.org/) publishing format
+- Modern Python practices
+- Continuous integration and testing infrastructure
+- Updated external links and references
+
+**Preserved Content:**
+
+- Mathematical derivations and theoretical foundations
+- Pedagogical structure and learning philosophy
+- Appendices on truncation errors and finite difference formulas
+
+### Acknowledgment
+
+This adaptation was prepared by Gerard J. Gorman (Imperial College London) in collaboration with the Devito development team.
+
+Professor Hans Petter Langtangen passed away in October 2016. His profound contributions to computational science education continue to benefit students and practitioners worldwide. This adaptation aims to honor his legacy by bringing his pedagogical approach to modern tools.
+
+---
+
+## Original Preface
+
+*The following preface is from the original work by Langtangen and Linge.*
+
 There are so many excellent books on finite difference methods for
 ordinary and partial differential equations that writing yet another
 one requires a different view on the topic. The present book is not
@@ -241,7 +285,7 @@ stated, even if it was already met in another chapter.
 
 All program and data files referred to in this book are available
 from the book's primary web site:
-URL: <https://github.com/hplgit/fdm-book/>.
+URL: <https://github.com/devitocodes/devito_book/>.
 
 ### Acknowledgments
 

index.qmd

@@ -4,12 +4,20 @@ This book teaches finite difference methods for solving partial differential equ
 
 ## About this Edition {.unnumbered}
 
-This is the modernized edition of *Finite Difference Computing with PDEs - A Modern Software Approach*, originally authored by Hans Petter Langtangen and Svein Linge. This edition features:
+This is an adaptation of *[Finite Difference Computing with PDEs: A Modern Software Approach](https://doi.org/10.1007/978-3-319-55456-3)* by Hans Petter Langtangen and Svein Linge (Springer, 2017). This Devito edition features:
 
 - **[Devito](https://www.devitoproject.org/)** - A domain-specific language for symbolic PDE specification and automatic code generation
 - **[Quarto](https://quarto.org/)** - Modern scientific publishing for web and PDF output
 - **Modern Python** - Type hints, testing, and CI/CD practices
 
+Adapted by Gerard J. Gorman (Imperial College London).
+
+## License {.unnumbered}
+
+[![CC BY 4.0](https://img.shields.io/badge/License-CC%20BY%204.0-lightgrey.svg)](https://creativecommons.org/licenses/by/4.0/)
+
+This work is licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), the same license as the original work.
+
 ## What is Devito? {.unnumbered}
 
 Devito allows you to write PDEs symbolically and automatically generates optimized finite difference code:
@@ -19,6 +27,7 @@ from devito import Grid, TimeFunction, Eq, Operator
 
 grid = Grid(shape=(101,), extent=(1.0,))
 u = TimeFunction(name='u', grid=grid, time_order=2, space_order=2)
+c = 1.0  # wave speed
 
 # Write the wave equation symbolically
 eq = Eq(u.dt2, c**2 * u.dx2)