Plan To Throw One Away YOU WILL ANYHOW CHAPTER 11 Pilot Plant Three phases of plant production Design Plant Pilot Plant Production.
Download ReportTranscript Plan To Throw One Away YOU WILL ANYHOW CHAPTER 11 Pilot Plant Three phases of plant production Design Plant Pilot Plant Production.
Slide 1
Plan To Throw One Away
YOU WILL ANYHOW
CHAPTER 11
Slide 2
Pilot Plant
Three phases of plant production
Design Plant
Pilot Plant
Production Plant
Slide 3
Throwaway System
Failed concept in system programming
On schedule delivery often means the first thing built
Barely useable
Often follow-up systems are needed
Question: Build a throwaway system in advance or
deliver it to the customer?
Slide 4
Results of Implementing a Throwaway
Buys builders time
Agony for customers
Distraction for builders by customers
Bad reputation for product and builders
Throwing away the
Throwaway
Giving the throwaway
to the customer
Slide 5
The Only Constancy is Change
Delivers satisfaction of a users needs rather than any
tangible product. And that the users perception of
that need will change as programs are built and used.
Product change is inevitable. The programmer must
be prepared for it rather than assuming it won’t
happen.
Slide 6
Plan the System for Change
Modularization
Extensive subroutines
Precise and complete definition of interfaces
All with complete documentation
Self-documenting in high-level languages reduces
errors
Compile-time operations to include standard
declerations
Slide 7
Plan the Organization for Change
Broader job assignments to make workers more
flexible
Large projects need multiple lead programmers
under the manager
The boss must keep his managers flexible as their
talents allow
Workers should be able to temporarily handle the
workload for anyone in the project both up and down
the ladder
Slide 8
Two Steps Forward One Step Back
Maintenance costs are usually 40% more than
development costs
The more users the more bugs are found
Fixing a defect has a high chance to cause another
Regression Testing takes previous battery of tests
and tests them against the new version of the system
Hence the importance of addressing problems early
Slide 9
One Step Forward One Step Back
With large systems: as the number of fixes increase
there will eventually be a point were these fixes will
not gain any ground and new problems will arise
from them
The system while technically still useable has worn
out and an entirely new system needs to take over
Slide 10
Conclusion
BETA
Plan To Throw One Away
YOU WILL ANYHOW
CHAPTER 11
Slide 2
Pilot Plant
Three phases of plant production
Design Plant
Pilot Plant
Production Plant
Slide 3
Throwaway System
Failed concept in system programming
On schedule delivery often means the first thing built
Barely useable
Often follow-up systems are needed
Question: Build a throwaway system in advance or
deliver it to the customer?
Slide 4
Results of Implementing a Throwaway
Buys builders time
Agony for customers
Distraction for builders by customers
Bad reputation for product and builders
Throwing away the
Throwaway
Giving the throwaway
to the customer
Slide 5
The Only Constancy is Change
Delivers satisfaction of a users needs rather than any
tangible product. And that the users perception of
that need will change as programs are built and used.
Product change is inevitable. The programmer must
be prepared for it rather than assuming it won’t
happen.
Slide 6
Plan the System for Change
Modularization
Extensive subroutines
Precise and complete definition of interfaces
All with complete documentation
Self-documenting in high-level languages reduces
errors
Compile-time operations to include standard
declerations
Slide 7
Plan the Organization for Change
Broader job assignments to make workers more
flexible
Large projects need multiple lead programmers
under the manager
The boss must keep his managers flexible as their
talents allow
Workers should be able to temporarily handle the
workload for anyone in the project both up and down
the ladder
Slide 8
Two Steps Forward One Step Back
Maintenance costs are usually 40% more than
development costs
The more users the more bugs are found
Fixing a defect has a high chance to cause another
Regression Testing takes previous battery of tests
and tests them against the new version of the system
Hence the importance of addressing problems early
Slide 9
One Step Forward One Step Back
With large systems: as the number of fixes increase
there will eventually be a point were these fixes will
not gain any ground and new problems will arise
from them
The system while technically still useable has worn
out and an entirely new system needs to take over
Slide 10
Conclusion
BETA