https://wiki.kram.nz/index.php?action=history&feed=atom&title=SE462%3A2007-07-23SE462:2007-07-23 - Revision history2026-04-29T22:58:09ZRevision history for this page on the wikiMediaWiki 1.45.3https://wiki.kram.nz/index.php?title=SE462:2007-07-23&diff=38&oldid=prevMark: New page: == SE462 Meeting of 23 July 2007 == === Alloy === * Everything in Alloy is a set of tuples. A basic datatype is a set of tuples. * There are NO numbers in Alloy. * ATOMS exist.. Scope {B...2008-02-15T19:46:47Z<p>New page: == SE462 Meeting of 23 July 2007 == === Alloy === * Everything in Alloy is a set of tuples. A basic datatype is a set of tuples. * There are NO numbers in Alloy. * ATOMS exist.. Scope {B...</p>
<p><b>New page</b></p><div>== SE462 Meeting of 23 July 2007 ==<br />
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=== Alloy ===<br />
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* Everything in Alloy is a set of tuples. A basic datatype is a set of tuples.<br />
* There are NO numbers in Alloy.<br />
* ATOMS exist.. Scope {Book 0, Book 1, Book 2...<br />
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* Book = { (Book 0, Book 1, Book 2) }<br />
* addr = { (Book 0, Name 1, Addr 2), (Book 0, Name 2, Addr 2) }<br />
* names = { (Book 0, Name 0), (Book 0, Name 1), (Book 0, Name 2) }<br />
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=== Lab: 1 ===<br />
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* Tutor - Scott<br />
* Tues 1-3pm in Ground floor lab<br />
* a) Exercise in relation types, b) What types to use<br />
* Do exercise & WRITE UP a lab report, we will have a discussion on this in class.<br />
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== Dot Operator ==<br />
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* b.addr => dot operator<br />
first = {(Book 0)}<br />
* n->t<br />
{ (N0) } -> { (Addr0) } = { (N0, Addr0) }<br />
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== Set Intersection ==<br />
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* Name & t<br />
{ (N0), (N1), (N2) } & {(N0)} = {(N0)}<br />
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== Set Difference a - b ==<br />
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{ (N0), (N1), (N2) } - {(N0)} = { (N1), (N2) }<br />
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== Union a + b ==<br />
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{ (N0), (N1), (N2) } + {(N0)} = { (N0), (N1), (N2) }<br />
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== Binary Relations ==<br />
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* Functional, Non injective<br />
* Injective, Non fuctional<br />
* Injective, Functional<br />
* Non injective, Non functional<br />
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== Domain & Range ==<br />
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* Domain = Right side of the relation<br />
* Range = Left side of the relation<br />
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* For domain or range, we join on univ set<br />
* Domain (rel) = rel.univ<br />
* Range (rel) = univ.rel<br />
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* dot(join) . or [ ] <br />
**a.b is b[a]<br />
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== Transitive Closure ==<br />
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* Given rel, '''^rel''' is transitive closure<br />
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== Reflective ==<br />
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* Given rel, '''*rel''' (includes iden)<br />
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== Arithmetic ==<br />
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* Alloy can do SOME arithmetic<br />
** # a + # b > # c<br />
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* Integers are atoms.. 1,2,3,...<br />
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* Everything is a RELATION<br />
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[[User:Sbas022|Sbas022]] 15:22, 24 July 2007 (NZST)</div>Mark