Programming Languages As difficult to discuss rationally as religion or politics. Prone to extreme statements devoid of data. Examples: \It is practically impossible to teach good programming to students that have had a prior exposure to BASIC; as potential programmers they are mentally mutilated beyond hope of regeneration.\(Dijkstra)

Difficult Person Hostile-aggressie Bullies, cverwhelms, and intimidates cthers nd up to the hostile ade frot atoers-can t accept feedback on t rush into the worst thing that coul happen?)

opyright Nancy Leveson, Sept. 1999 Stage 1: Forming Team members begin to discover what behaviors are acceptable Usually highly unstructured environment Attempt to identify tasks, how to accomplish them Decisions on what information is needed Hesitant participation

Can programming language influence correctness? anguages affect the way we think about problems The tools we use have a profound(and devious) influence on our thinking habits, and, therefore on our thinking abilities?

1. When you can measure what you are speaking about, and can express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowleage is of a meagre and unsatisfactory kind: It may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the stage of science. Lord Kelvin, a physicist

Fairly primitive and predictive power limited Function Points Count number of inputs and output, user interactions, external interfaces files used Assess each for complexity and multiply by a weighting factor Used to predict size or cost and to assess project productivity

Reuse (Assume have source code, not a commercial product) Ariane 5. Therac-25. British AtC Expectation Significantly lower development costs and time. Amortize costs among all users or uses Assumptions

A Testing EXercise (From Glenford Myers: The Art of Software Testing A program reads three integer values from a card. The three values are interpreted as representing the lengths of the sides of a triangle. The program prints a message that states whether the triangle is scalene iso

Formal design Reviews Associated with each of documentation phases Evaluate with respect to Customer requirements Prescribed standards and practices Contractual requirements

State Machine specifications Define behavior using states and transitions between states