Reasoned Programming

Presents informal way of attempting a mathematical proof of reliability to make sure that our computer programs will work reliably. Also shows the benefits of the approach even without strict formality.

**Tag(s):**
Formal Methods

**Publication date**: 01 Jan 1994

**ISBN-10**:
n/a

**ISBN-13**:
n/a

**Paperback**:
n/a

**Views**: 18,249

**Type**: N/A

**Publisher**:
n/a

**License**:
n/a

**Post time**: 20 Sep 2006 08:55:09

Reasoned Programming

Presents informal way of attempting a mathematical proof of reliability to make sure that our computer programs will work reliably. Also shows the benefits of the approach even without strict formality.

Book Excerpts:

Can we ever be sure that our computer programs will work reliably? One approach to this problem is to attempt a mathematical proof of reliability, and this has led to the idea of Formal Methods: if you have a formal, logical specification of the properties meant by 'working reliably', then perhaps you can give a formal mathematical proof that the program (presented as a formal text) satisfies them.

Of course, this is by no means trivial. Before we can even get started on a formal proof we must turn the informal ideas intended by 'working reliably' into a formal specification, and we also need a formal account of what it means to say that a program satisfies a specification (this amounts to a semantics of the programming language, an account of the meaning of programs). None the less, Formal Methods are now routinely practised by a number of software producers.

The aim of this book is to present informal formal methods, showing the benefits of the approach even without strict formality although we use logic as a notation for the specifications, we rely on informal semantics -- a programmer's ordinary intuitions about what small, linear stretches of code actually do -- and we use proofs to the level of rigour of ordinary mathematics.

This can, of course, serve as a first introduction to strict Formal Methods, but it should really be seen much more broadly. The benefits of Formal Methods do not accrue just from the formality. The very effort of writing a specification prior to the coding focuses attention on what the user wants to get out of the program, as opposed to what the computer has to do, and the satisfaction proof, even if informal, expresses our idea of how the algorithm works. This does not require support tools, and the method -- which amounts really to methodical commenting -- is practicable in all programming tasks.

Book Structures:

The book is divided into two complementary parts, the first on Programming and the second on Logic. Though they are both about logical reasoning, the first half concerns the ideas about programs that the reasoning is intended to capture, while the second half is more about the formal machinery. The distinction is somewhat analogous to that often seen in books about programming languages a first part is an introduction to programming using the language, and a second part is a formal report on it.

To read the book from scratch, one would most likely read the two parts in parallel, and this is in fact how the material was used for the computer science course at Imperial College. However, the division into two reasonably disjoint parts means that people who already have some background in logic can see the programming story told without interruption.

Can we ever be sure that our computer programs will work reliably? One approach to this problem is to attempt a mathematical proof of reliability, and this has led to the idea of Formal Methods: if you have a formal, logical specification of the properties meant by 'working reliably', then perhaps you can give a formal mathematical proof that the program (presented as a formal text) satisfies them.

Of course, this is by no means trivial. Before we can even get started on a formal proof we must turn the informal ideas intended by 'working reliably' into a formal specification, and we also need a formal account of what it means to say that a program satisfies a specification (this amounts to a semantics of the programming language, an account of the meaning of programs). None the less, Formal Methods are now routinely practised by a number of software producers.

The aim of this book is to present informal formal methods, showing the benefits of the approach even without strict formality although we use logic as a notation for the specifications, we rely on informal semantics -- a programmer's ordinary intuitions about what small, linear stretches of code actually do -- and we use proofs to the level of rigour of ordinary mathematics.

This can, of course, serve as a first introduction to strict Formal Methods, but it should really be seen much more broadly. The benefits of Formal Methods do not accrue just from the formality. The very effort of writing a specification prior to the coding focuses attention on what the user wants to get out of the program, as opposed to what the computer has to do, and the satisfaction proof, even if informal, expresses our idea of how the algorithm works. This does not require support tools, and the method -- which amounts really to methodical commenting -- is practicable in all programming tasks.

Book Structures:

The book is divided into two complementary parts, the first on Programming and the second on Logic. Though they are both about logical reasoning, the first half concerns the ideas about programs that the reasoning is intended to capture, while the second half is more about the formal machinery. The distinction is somewhat analogous to that often seen in books about programming languages a first part is an introduction to programming using the language, and a second part is a formal report on it.

To read the book from scratch, one would most likely read the two parts in parallel, and this is in fact how the material was used for the computer science course at Imperial College. However, the division into two reasonably disjoint parts means that people who already have some background in logic can see the programming story told without interruption.

Tweet

About The Author(s)

No information is available for this author.

No information is available for this author.

No information is available for this author.

No information is available for this author.

Book Categories

Computer Science
Introduction to Computer Science
Introduction to Computer Programming
Algorithms and Data Structures
Artificial Intelligence
Computer Vision
Machine Learning
Neural Networks
Game Development and Multimedia
Data Communication and Networks
Coding Theory
Computer Security
Information Security
Cryptography
Information Theory
Computer Organization and Architecture
Operating Systems
Image Processing
Parallel Computing
Concurrent Programming
Relational Database
Document-oriented Database
Data Mining
Big Data
Data Science
Digital Libraries
Compiler Design and Construction
Functional Programming
Logic Programming
Object Oriented Programming
Formal Methods
Software Engineering
Agile Software Development
Information Systems
Geographic Information System (GIS)

Mathematics
Mathematics
Algebra
Abstract Algebra
Linear Algebra
Number Theory
Numerical Methods
Precalculus
Calculus
Differential Equations
Category Theory
Proofs
Discrete Mathematics
Theory of Computation
Graph Theory
Real Analysis
Complex Analysis
Probability
Statistics
Game Theory
Queueing Theory
Operations Research
Computer Aided Mathematics

Supporting Fields
Web Design and Development
Mobile App Design and Development
System Administration
Cloud Computing
Electric Circuits
Embedded System
Signal Processing
Integration and Automation
Network Science
Project Management

Operating System
Programming/Scripting
Ada
Assembly
C / C++
Common Lisp
Forth
Java
JavaScript
Lua
Rexx
Microsoft .NET
Perl
PHP
R
Python
Rebol
Ruby
Scheme
Tcl/Tk

Miscellaneous
Sponsors