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Item Details
| Title:
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Z USER WORKSHOP, YORK, 1991
PROCEEDINGS OF THE SIXTH ANNUAL Z USER MEETING, YORK, 16-17 DECEMBER 1991 |
| By: |
J.E. Nicholls (Editor) |
| Format: |
Paperback |
| List price:
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£76.50 |
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We currently do not stock this item, please contact the publisher directly for
further information.
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| ISBN 10: |
354019780X |
| ISBN 13: |
9783540197805 |
| Publisher: |
SPRINGER-VERLAG BERLIN AND HEIDELBERG GMBH & CO. KG |
| Pub. date: |
6 August, 1992 |
| Edition: |
Softcover reprint of the original 1st ed. 1992 |
| Series: |
Workshops in Computing |
| Pages: |
408 |
| Description: |
Provides an overview of new developments in theoretical and practical aspects of Z. It should be of interest to academic and industrial researchers, as well as teachers of formal methods, and industrial software engineers. |
| Synopsis: |
In ordinary mathematics, an equation can be written down which is syntactically correct, but for which no solution exists. For example, consider the equation x = x + 1 defined over the real numbers; there is no value of x which satisfies it. Similarly it is possible to specify objects using the formal specification language Z [3,4], which can not possibly exist. Such specifications are called inconsistent and can arise in a number of ways. Example 1 The following Z specification of a functionf, from integers to integers "f x : ~ 1 x ~ O* fx = x + 1 (i) "f x : ~ 1 x ~ O* fx = x + 2 (ii) is inconsistent, because axiom (i) gives f 0 = 1, while axiom (ii) gives f 0 = 2. This contradicts the fact that f was declared as a function, that is, f must have a unique result when applied to an argument. Hence no suchfexists. Furthermore, iff 0 = 1 andfO = 2 then 1 = 2 can be deduced! From 1 = 2 anything can be deduced, thus showing the danger of an inconsistent specification. Note that all examples and proofs start with the word Example or Proof and end with the symbol.1. |
| Illustrations: |
biography |
| Publication: |
Germany |
| Imprint: |
Springer-Verlag Berlin and Heidelberg GmbH & Co. K |
| Returns: |
Returnable |
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