From Muddling to Modelling
6 likes4,572 views
The document discusses the transition from muddling to modelling in various fields such as software and engineering, emphasizing the importance of clear definitions and representations in coding and modelling. It highlights the need for instantiation and validation of abstractions, while also addressing the complexities and challenges of current modelling practices. Additionally, it suggests that better semantics and reduced speculation could enhance the effectiveness of software specifications.
![Pragmatic kludge: design time
The Power Type pattern
Class : Mammal
Class : AnimalSpecies
dateOfBirth
maxAge [1] [*]
configuration
A.S. : Dog
{20 years}
time? Class : Dog
isPoliceDog [2]
Class : Cat
[2]
A.S. : Cat
{30 years} [*] [*]
Dog : Jack Cat : Coco
Observation: Today’s
{1/5/03, yes} {4/3/07}
Dog : Susie Cat : Peter
software contains a {1/2/00, no} {10/9/98}
significant amount of
avoidable, spurious
complexity run time](https://image.slidesharecdn.com/frommuddlingtomodelling-100403135523-phpapp01/85/From-Muddling-to-Modelling-21-320.jpg)
![object oriented model A object oriented model B
(modelling instantiation via association) (modelling instantiation via specialisation)
Class : Mammal
Class : AnimalSpecies Class : Animal
[2] dateOfBirth
maxAge dateOfBirth
[1] [*] problem
no species
[*]
data
A.S. : Dog
{20 years} Class : Dog Class : Cat
isPoliceDog [2] [2]
A.S. : Cat
{30 years} [*] [*]
Dog : Jack Cat : Coco
Animal : Jack Animal : Coco {1/5/03, yes} {4/3/07}
{1/5/03} {4/3/07}
Dog : Susie Cat : Peter
Animal : Susie Animal : Peter {1/2/00, no} {10/9/98}
{1/2/00} {10/9/98}
problem
no species-specific
instance data problem
precision of links](https://image.slidesharecdn.com/frommuddlingtomodelling-100403135523-phpapp01/85/From-Muddling-to-Modelling-34-320.jpg)
![object oriented model C
(Power Type pattern)
Class : Mammal
Class : AnimalSpecies
dateOfBirth
maxAge [1] [*]
problem
Fragmentation of
concepts
A.S. : Dog
{20 years} Class : Dog Class : Cat
isPoliceDog [2] [2]
A.S. : Cat
{30 years} [*] [*]
problem
Spurious complexity
Dog : Jack Cat : Coco
{1/5/03, yes} {4/3/07}
Dog : Susie Cat : Peter
{1/2/00, no} {10/9/98}](https://image.slidesharecdn.com/frommuddlingtomodelling-100403135523-phpapp01/85/From-Muddling-to-Modelling-35-320.jpg)
![object oriented model C design time
(Power Type pattern)
Class : Mammal
Class : AnimalSpecies
dateOfBirth
maxAge [1] [*]
configuration
A.S. : Dog
{20 years}
time? Class : Dog
isPoliceDog [2]
Class : Cat
[2]
A.S. : Cat
{30 years} [*] [*]
Dog : Jack Cat : Coco
{1/5/03, yes} {4/3/07}
Dog : Susie Cat : Peter
{1/2/00, no} {10/9/98}
run time](https://image.slidesharecdn.com/frommuddlingtomodelling-100403135523-phpapp01/85/From-Muddling-to-Modelling-36-320.jpg)
![multi-level modelling Vertex : AnimalSpecies system
precise instantiation semantics
role based binding times
maxAge
isAbstract : no design time
modularity
simplicity
instantiation ...
AnimalSpecies : Mammal species
establishes connections between
two levels of abstraction that
define different binding times
maxAge : 150
isAbstract : yes
dateOfBirth
configuration
time
generalisation/specialisation ...
expresses the commonalities and a consistent instantiation
variabilities between the concepts mechanism at all levels
relevant to a specific binding time and unlimited levels of
AnimalSpecies : Dog AnimalSpecies : Cat
instantiation
maxAge : 20 [2] maxAge : 30 [2]
isAbstract : no isAbstract : no
isPoliceDog [*] [*]
treatment time
Dog : Jack Dog : Susie Cat : Coco Cat : Peter
dateOfBirth : 1/5/03 dateOfBirth : 1/2/00 dateOfBirth : 4/3/07 dateOfBirth : 10/9/98
isPoliceDog : yes isPoliceDog : no](https://image.slidesharecdn.com/frommuddlingtomodelling-100403135523-phpapp01/85/From-Muddling-to-Modelling-38-320.jpg)
More Related Content
![UNIT 3 INTERNATIONAL BUSINESS [Autosaved].pptx](https://cdn.slidesharecdn.com/ss_thumbnails/unit3internationalbusinessautosaved-250828123159-46ee6bdc-thumbnail.jpg?width=560&fit=bounds)
From Muddling to Modelling
- 1. From Muddling to Modelling in software, economics, engineering, science
- 2. instance ? class ? encrypting ? coding ? modelling ? muddling ? Golf ABC 123 model ? object ?
- 3. Dictionary definition: to code express (a statement or communication) in an indirect way Coding can be viewed as having to deal with someone else’s representation (program notation or otherwise) Dictionary definition: to model devise a representation, especially a mathematical one of (a phenomenon or system) Modelling can be viewed as dealing with a representation that is fit for purpose
- 4. Notation Semantics ? Golf ABC 123 ABC 12 3
- 5. Golf ABC 123 ABC 1 23 3 ABC 12
- 6. A familiar setting from elementary school maths ABC 1 23 3 ABC 12
- 7. cars Observation: Modelling of abstractions relies on concepts from pure mathematics, it requires no statistics or other applied mathematics ABC 1 23 3 ABC 12
- 8. Observation: Models are a way of referring to useful sets or subsets in a domain Observation: The elements of a set may change over time Definition: Golf A query is a function that Golf returns the content of a set at cars a given point in time
- 9. Observation: Only one car with reg # ABC 123 can exist at any given time cars with reg # ABC 123 ABC 123 Definition: An instance is a set that contains one and ABC 1 only one element at 23 ABC 12 3 any given point in time
- 10. model Adding another level of subsets model instance model Golf ABC 123
- 11. Definition: Instantiation is a model function that returns an instance model instance model instantiation Golf of ABC 123
- 12. model instantiation of Observation: If the intermediate subsets cars and Golf are not relevant to instance our model, we can use an instantiation function from a higher level of abstraction ABC 123
- 13. Simplifying the notation subset of subset of Golf ABC 123 instance of
- 14. View points subset of subset of Golf sales ABC 123 person ABC 123 is an instance of Golf
- 15. View points subset of Golf is an instance of cars engineer Golf sales ABC 123 person ABC 123 is an instance of Golf
- 16. View points cars is an instance of objects software platform Golf is an instance of cars engineer Golf sales ABC 123 person ABC 123 is an instance of Golf
- 17. engineer Golf Golf is an ABC instance 123 of ca is an rs insta nce o f Golf Communication ? ABC 123 Golf sales person
- 18. Abstractions must be validated via instantiation Golf abstract instantiate ABC 1 23 engineer sales person
- 19. Notation Semantics Golf ABC 1 ABC 123 23
- 20. No support for multi-level instantiation in any industry standard modelling/programming language ! cars is an instance of objects engineer Golf Golf is an instance of cars sales person ABC 123 is an instance of Golf ABC 123
- 21. Pragmatic kludge: design time The Power Type pattern Class : Mammal Class : AnimalSpecies dateOfBirth maxAge [1] [*] configuration A.S. : Dog {20 years} time? Class : Dog isPoliceDog [2] Class : Cat [2] A.S. : Cat {30 years} [*] [*] Dog : Jack Cat : Coco Observation: Today’s {1/5/03, yes} {4/3/07} Dog : Susie Cat : Peter software contains a {1/2/00, no} {10/9/98} significant amount of avoidable, spurious complexity run time
- 23. Notation matters, often less is more ? U not quite ? correct ... U ? U U ( )
- 24. Potentially useful semantics <=> ( ABC 123 : ) U ( ... ) U ... Joe <=> ( ABC 123 : ) U ( ... ) U ... Joe <=> ( :( U ABC 123 )) U ... Joe
- 25. We constantly rely on speculative interpretation <=> airplane or aircraft ? <=> commercial aircraft ? <=> ship or boat ? <=> ferry or cruise ship ? <=> car ferry ? <=> paddler or boat ? Observation: It works 80% of the time
- 26. Perhaps 80% is not quite good enough for software specification ! Golf abstract instantiate ABC 1 23 Observation: We need less speculation and much more validation via instantiation !
- 27. Is natural language any better? use case step (end user needs)
- 28. Is code any better? use case step (end user needs) software design (voodoo) whizBangTech.createStandardOrder(whizBangTech.createPartner(“Joe”), vwGolf, blue, 1); code (implementation)
- 29. Is code any better? The code is the design. Yeah, right! use case step (end user needs) software design (voodoo) whizBangTech.createStandardOrder(whizBangTech.createPartner(“Joe”), vwGolf, blue, 1); code (implementation)
- 30. model (specification) use case step (end user needs) Automation (generation, execution) whizBangTech.createStandardOrder(whizBangTech.createPartner(“Joe”), vwGolf, blue, 1); code (implementation)
- 31. model (specification) use case step (end user needs) whizBangTech.createStandardOrder(whizBangTech.createPartner(“Joe”), vwGolf, blue, 1)); code (implementation)
- 32. Observation: Instantiation links do not adhere to the simplistic rules of the traditional class/object paradigm ... under-specified instance of the VWGolf product line nearly fully-specified instance only here the instance is fully-specified Observation: Partial, incremental instantiation is common in product lines
- 34. object oriented model A object oriented model B (modelling instantiation via association) (modelling instantiation via specialisation) Class : Mammal Class : AnimalSpecies Class : Animal [2] dateOfBirth maxAge dateOfBirth [1] [*] problem no species [*] data A.S. : Dog {20 years} Class : Dog Class : Cat isPoliceDog [2] [2] A.S. : Cat {30 years} [*] [*] Dog : Jack Cat : Coco Animal : Jack Animal : Coco {1/5/03, yes} {4/3/07} {1/5/03} {4/3/07} Dog : Susie Cat : Peter Animal : Susie Animal : Peter {1/2/00, no} {10/9/98} {1/2/00} {10/9/98} problem no species-specific instance data problem precision of links
- 35. object oriented model C (Power Type pattern) Class : Mammal Class : AnimalSpecies dateOfBirth maxAge [1] [*] problem Fragmentation of concepts A.S. : Dog {20 years} Class : Dog Class : Cat isPoliceDog [2] [2] A.S. : Cat {30 years} [*] [*] problem Spurious complexity Dog : Jack Cat : Coco {1/5/03, yes} {4/3/07} Dog : Susie Cat : Peter {1/2/00, no} {10/9/98}
- 36. object oriented model C design time (Power Type pattern) Class : Mammal Class : AnimalSpecies dateOfBirth maxAge [1] [*] configuration A.S. : Dog {20 years} time? Class : Dog isPoliceDog [2] Class : Cat [2] A.S. : Cat {30 years} [*] [*] Dog : Jack Cat : Coco {1/5/03, yes} {4/3/07} Dog : Susie Cat : Peter {1/2/00, no} {10/9/98} run time
- 37. The solution
- 38. multi-level modelling Vertex : AnimalSpecies system precise instantiation semantics role based binding times maxAge isAbstract : no design time modularity simplicity instantiation ... AnimalSpecies : Mammal species establishes connections between two levels of abstraction that define different binding times maxAge : 150 isAbstract : yes dateOfBirth configuration time generalisation/specialisation ... expresses the commonalities and a consistent instantiation variabilities between the concepts mechanism at all levels relevant to a specific binding time and unlimited levels of AnimalSpecies : Dog AnimalSpecies : Cat instantiation maxAge : 20 [2] maxAge : 30 [2] isAbstract : no isAbstract : no isPoliceDog [*] [*] treatment time Dog : Jack Dog : Susie Cat : Coco Cat : Peter dateOfBirth : 1/5/03 dateOfBirth : 1/2/00 dateOfBirth : 4/3/07 dateOfBirth : 10/9/98 isPoliceDog : yes isPoliceDog : no
- 39. More Information The role of artefacts tiny.cc/artefacts Model Oriented Domain Analysis tiny.cc/domainanalysis Multi-Level Modelling tiny.cc/gmodel tiny.cc/sematpos_jbe, SEMAT tiny.cc/sematslides_jbe Denotational Semantics tiny.cc/densem Thank you! Jorn Bettin jbe @ sofismo.ch