Second meeting of the Interval Subroutine Library group
27 February to 4 March 2006

About the ISL project

The ISL Team

• Baker Kearfott, University of Louisiana at Lafayette (Project Leader)
• George Corliss, Marquette University (Schedule Organizer for this meeting)
• John Pryce, RMCS, Cranfield University
• Ned Nedialkov, McMaster University
• Spencer Smith, McMaster University  (Local Organizer for this meeting)

Meeting venue

Programme details

Issues to be considered include:

1. Progress
• Have we done what we said we would do at the previous meeting?
• What should our priorities be for the next meeting?
• What schedule should we set for specific delivarables (components that are aviailable publicly)? ( I believe we should have a near target date for a few simple deliverables, on the lowest level.)
• What should we be working on during the meeting?
2. Items to be resolved conclusively at the meeting:
• The protocol for testing (A written protocol that we can follow without qualms should emerge from the meeting.)
• A web interface delivery system (such as suggested by Ned;  we should produce a written document by the end of the meeting specifying how this is to be done.)
3. Mission:

The goal of the ISL project is to meet that need by providing a library of high quality interval-based tools. The qualities of interest for the ISL project include the following: correctness, reliability, robustness, performance (with respect to tight bounds, time efficiency and space efficiency), verifiability, productivity, usability, understandability, maintainability, reusability and portability. To achieve these qualities, the ISL project will use strategies that include writing documentation and providing support. To have a high quality library we need high quality documentation; that is, the documentation should have the qualities of being complete, consistent, correct, usable, verifiable, maintainable, and reusable. By providing support, the ISL project aims to improve the qualities of usability and understandability for the library.
• Concensus on Spencer's definitions
• Long-term goals
• Short-term goals
4. Product -- What will we deliver?
• Contents

We envision a layered library, with units organized into chapters:
• Level 0 -- Basic Interval Arithmetic Subroutines: Provides basic interval arithmetic, probably including
1. Arithmetic operations,
2. Constructors,
3. Comparison operators,
4. Simple input/output, and
5. Elementary functions (?)
Large overlap with the functionality provided by many current interval arithmetic packages.
• Level 1 -- Utilities: Provides capabilities frequently required by more general units, probably including
1. Additional (non-basic) interval arithmetic features,
2. Level 1 and level 2 BLAS,
3. Automatic differentiation,
4. Taylor model arithmetic,
5. Constraint propagation,
6. Linear systems,
7. etc.
Level 1 units are called by several units in Level 2.
• Level 2 -- Problem-solving routines: Approximate chapter outline of many textbooks in numerical analysis, probably including
1. Linear systems (more than in Level 1), including sparse and eigensystems.
2. Nonlinear systems,
3. Optimization,
4. Quadrature,
5. Statistics,
6. Ordinary differential equations,
7. Partial differential equations,
8. etc.
We expect that list to grow with time.
• Level 3 -- Applications: Not in the scope of ISL, but we strongly encourage applications developers to build on ISL.
5. Plan -- How will we accomplish that?
• Short-term plan: Gather, organize, and disseminate
• Step 1 -- Language standardization.
• Step 2 -- Pilot inclusion into \ISL.
• Step 3 -- Invite participation.
WHAT would we release?
• Long-term plan
• Issue: Language and environment
• Issue: Organizational structure
• Issue: Adding value
• Issue: Quality
• Issue: Licensing
• Issue: Publications
• Issue: Funding, e.g., NSF Baker uncovered
6. Partners -- How can you help?

Discussion of ``certification'' of codes such as Ned's goes here.
• Contributing author
• Chapter architect/editor
• Referee
• Applications development

External applications speakers

• John McPhee, U of Waterloo, http://sydewww.uwaterloo.ca/Faculty/CurrentTenured/McPhee/mcphee.html
• Douglas Moseley, U of Toronto, http://www.dro.facmed.utoronto.ca/English/Moseley-Douglas.html
• Jacques Carette, McMaster, http://www.cas.mcmaster.ca/~carette
• Mark Fairlamb, EnviroSim, http://www.envirosim.com/index_fla.php
• Paul Sermer, Ontario Power Generation

Accommodation

ISL Group members only