1. Questions?

2. From ( ) get:
1) 0
2) 64
3) 1000
4) ( )
5) ( )
6) ( )
7) (0 1)
8) ((0))
9) ( )
10) (60 0)

3. From (((a) b) c) get:
1) a
2) c
3) b
4) (a b)
5) (a (b c)))

4. From (a b c d e) get:
1) (d e)
2) 5
3) (a (b (c (d (e)))))
4) (e d c b a)
5) (a b c d)

5. From a get:
1) (a)
2) (a . a)
3) (a (a))
4) ((a) a)
5) (a ())

6. From a and (b c) get:
1) (a b c)
2) ((a) b c)
3) (a (b c))
4) (a c)
5) (c b a)

7. From (a b) and (c d) get:
1) (a b c d)
2) ((a b) c d)
3) ((a b)(c d))
4) (b a d c)
5) (a (b c) d)

8. (append '((1)) '(2 3))

9. ((1) 2 3)

10. (append '((2)(3)) '(4 5))

11. ((2) (3) 4 5)

12. (first '(((a)) (b c d e)))

13. ((A))

14. (rest '(((((f))))))

15. nil

16. (first '(rest (a b c)))

17. rest

18. (first (second '(((1 2))(2 3 4)((5 6 7)))))

19. 2

20. (second (first '(((1 2))(2 3 4)((5 6 7)))))

21. nil

22. Define a function AVERAGE that returns the average of 5 numbers:
(average ) returns 3.

23. (defun average (n1 n2 n3 n4 n5)
(coerce (/ (+ n1 n2 n3 n4 n5) 5) 'float))
; ? (average )
; 3.0
; ? (average )
; 3.2

24. Sonification Sound from data not intended to create sound.
Both scientific and artistic value.

25. Pleiades Large scale radio telescope
Ability to view data in standard ways
Ability to usefully hear data in order to find patterns otherwise not perceivable
Musically interesting sonifications
SETI (Search for Extraterrestrial Life)

26. Pleiades Data from the planet Jupiter Data selected by Cope
Data sonified by Peter Elsea (mid-80s)
Saturday night Pleiades by Cope
Sonification of planet Mars (2002 or so)

27. Sonification Where do you begin? Where do you go from there?
What do you want to have as output?

28. Divide and Conquer Find interesting data Ensure it’s diverse enough
Lispify it (listify)
Normalize the data to MIDI range
Produce cope-events.
Save as MIDI file and play.

29. Sonification
What criteria to use in finding data?

30. Data Astronomical Stocks Temperatures Seismological Measurements
Bit maps

31. DATA How do you get the data into musical shape?
The process is known as normalization
How do you achieve normalization?

32. Normalization Compare range of one list to another (/)
Multiply by known element of first list (minus it’s lowest range level)
Add in lower MIDI range
Round it to avoid floats
New MIDI note

33. Recursion
The ability of a function to do the same thing to an arbitrary length list of data
The ability of a function to call itself
The ability of a function to automatically stop at the end of its argument
The ability of a function to return the changed data in appropriate order

34. Add-One Data: ‘(1 2 3 4 5 6 7) Process: add one to each number
(cons (+ 1 7) ())
(cons (+ 1 6) (cons (+ 1 7) ())
(cons (+ 1 5) (cons (+ 1 6) (cons (+ 1 7) ())
And so on?

35. In other words
(cons n3 (cons n2 (cons n1 (cons n0 ())))

36. Recursion
(defun add-one (list-of-numbers)

37. Ending
You must have code to end the function first in order to make sure the function ends with an empty list as second argument to the final call to cons.

38. Continuation (defun add-one (list-of-numbers)
(if (null list-of-numbers) ()

39. Continuation (defun add-one (list-of-numbers)
(if (null list-of-numbers) ()
(cons (+ 1 (first list-of-numbers))

40. Continuation (defun add-one (list-of-numbers)
(if (null list-of-numbers) ()
(cons (+ 1 (first list-of-numbers))
(add-one (rest list-of-numbers))))

41. It works
? (add-one ‘( ))
( )