An Introduction to the J Programming Language
|revised July 2013|
|About this Book|
|Table of Contents|
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Copyright © Roger Stokes 2013. This material may be freely reproduced, provided that acknowledgment is made.
This book is meant to help the reader to learn the computer-programming language J.
My hope is that the book will be useful to a wide readership. Care is taken to introduce only one new idea at a time, to provide examples at every step, and to make the examples very simple. Even so, the experienced programmer will find much to appreciate in the radical simplicity and power of the J notation.
The scope of this book is the core J language defined in the J Dictionary. The coverage of the core language is meant to be relatively complete, covering (eventually) most of the Dictionary.
Hence the book does not cover topics such as graphics, plotting, GUI, and database covered in the J User Guide, nor does it cover the J Application Library . I should make clear what the aims of the book are not: neither to teach principles of programming, nor to study algorithms, or topics in mathematics or other subjects using J as a vehicle, nor to provide definitive reference material.
The book is organized as follows. Part 1 is a basic introduction which touches on a variety of themes. The aim is to provide the reader, by the end of Part 1, with an overview and a general appreciation of the J language. The themes introduced in Part 1 are then developed in more depth and detail in the remainder of the book.
All the examples have been executed with J701.
Part 1: Getting Acquainted
| 1: Basics |
2: Lists and Tables
3: Defining Functions
4: Scripts and Explicit Functions
Part 2: Arrays
| 5: Building Arrays |
Part 3: Defining Functions: Verbs
| 8: Composing Verbs|
9: Trains of Verbs
10: Conditional and Other Forms
11: Tacit Verbs Concluded
12: Explicit Verbs
Part 4: Defining Functions: Operators
| 13: Explicit Operators|
15: Tacit Operators
Part 5: Structural Functions
| 16: Rearrangements |
17: Patterns of Application
18: Sets, Classes and Relations
Part 6: Numerical and
| 19: Numbers|
20: Scalar Numerical Functions
21: Factors and Polynomials
22: Vectors and Matrices
Part 7: Names and Objects
| 24: Names and Locales|
25: Object-Oriented Programming
Part 8: Facilities
| 26: Script Files|
27: Representations and Conversions
28: Data Files
29: Error Handling
30: Sparse Arrays
| A1: Evaluating Expressions|
A2: Collected Terminology