1 software engineering discussion for scec useit intern program phil maechling 26 may 2005...

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Software Engineering Discussion for SCEC UseIT Intern Program

Phil Maechling26 May 2005maechlin@usc.eduhttp://www.scec.org/cme

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Creating Over Consuming

Science is a creative activity.

Developing software is a creative activity.

Try them out this summer. Give them a chance. You could find something meaningful to you personally.

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Simple is Good

"Any darn fool can make something complex; it takes a genius to make something simple."- Pete Seeger

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Types of Software Development

You can develop software a couple of ways. Each has value and can be satisfying.

• Hacker Approach

• Engineer Approach

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Power of Programming

Hacker Potential - One person, alone in a room with a computer, and compiler, can change the world.

(Note: Others occupations with this power include writers, musicians, artists, scientists)

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Hacker Hero Gallery

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Power of Programming

One person, alone in a room with a computer, and compiler, can change the world.

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Hacker Mentality

Hackers consider themselves something of an elite (a meritocracy based on ability), though one to which new members are gladly welcome.

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Hacker Hero Gallery

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Hacker Essential Reading

• Hackers – Steven Levy

• The New New Thing – Michael Lewis

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The Power of Engineering

Engineer Potential - By organizing group efforts, managing the communication between members, large scale tools and system can be produced.

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Engineer Hero Gallery

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Engineer Hero Gallery

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Engineer Hero Gallery

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Engineering Challenge is Working With Groups of People

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Engineering Challenge is “Does it Work” is well Defined

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Software Engineering Essential Reading

• Mythical Man Months – Robert Brooks

• The Soul of a New Machine – Tracy Kidder

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Difference Between Hacking and Engineering is Scale

There is a huge difference between what one person can build and a group can build.

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One Person Scale

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A Group of People

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The Power of Organization

Engineering – Cost of software systems are equivalent to large buildings.

50K – Small Program, 2BRM House Wichita 10M – SCEC/CME, 5 Story Office Building200M – Healthcare Billing system, 60 Story

Building

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Software Engineering Class in School

• Does not teach Programming! Assumes you already know how to program.

• Describes how large projects are organized, planned, scheduled, cost estimated.

• Usually a heavy load class, group projects, software development task and often competition between groups.

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Software Engineering Issues

• How do we define what the system should do (requirements)?

• How much will system cost?

• How long will it take to develop?

• How do we organize the group (who does what)?

• How do we verify system is giving correct answer?

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Software Development as a Process

• Accumulated wisdom in the field says software development should be treated as a process.

• The process is repeated, even though the product being developed, changes.

• While there are many Software Engineering Processes. They typically deal with the same issues including: requirements, cost, schedule, testing, validation, managing changes.

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Software Development as a Process

1 - Initial  : At maturity level 1, processes are usually ad hoc and chaotic.

2 - Repeatable : At maturity level 2, Software development successes are repeatable.

3 - Defined  : At maturity level 3, processes are well characterized and understood, and are described in standards, procedures, tools, and methods.

4 - Managed  : Using precise measurements, management can effectively control the software development effort

5 - Optimizing  : Maturity level 5 focuses on continually improving process performance

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Standard Aerospace Software Process

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Standard Aerospace Software Process

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Software Development Process

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Software Times Changed

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Software Times Changed

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Revolutions Require an Alternative to Status Quo

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Expression of Values

The four main values of the agile methods are:

1. Individuals and interactions over processes and tools

2. Working software over comprehensive documentation

3. Customer collaboration over contract negotiation

4. Responding to change over following a plan

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Agile/XP Process/Practices

1. Planning Game 2. Small Releases 3. Metaphor 4. Simple Design 5. Testing 6. Continuous Integration 7. Pair Programming 8. Collective Ownership 9. Refactoring 10. 40-Hour Week 11. On-Site Customer 12. Coding Standards

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Software Engineering This Summer

• Enginering requires more than Programming. Not every has to program.

• Group has room for both hackers and engineers

• No full time hackers. Some engineering required of everyone using an agile method

• Show skill, tolerance, patience, work ethic, and precedence of group interests over individual interests.

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Software Engineering This Summer

• Personal skill development this summer should include skill of working with a group.

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Software Engineering This Summer

• Creating a functional and useful software system from a group this large will require an engineering process.

• Please participate with us in our Engineering Process.

• Our Engineering Process should reflect our values: Learning, People, Communications, Science, Creativity, Usefulness.