sicp/zapiski/1_g1smo.org

Zapiski #1 srečanja programerskega bralnega krožka SICP

Zanimivi izseki

str. 9

Every reader should ask himself periodically "Toward what end, toward what end?" — but do not ask it too often lest you pass up the fun of programming for the constipation of bittersweet philosophy.

Lisp is a survivor, having been in use for about a quarter of a century.

str. 11

It is better to have 100 functions operate on one data structure than to have 10 functions operate on 10 data structures.

str. 18

Thus, programs must be written for people to read, and only incidentally for machines to execute.

str. 19

Underlying our approach to this subject is our conviction that "computer science" is not a science and that its significance has little to do with computers.

str. 27

Finally, we would like to acknowledge the support of the organizations that have encouraged this work over the years, including support from Hewlett-Packard, made possible by Ira Goldstein and Joel Birnbaum, and support from DARPA, made possible by Bob Kahn.

Bob Kahn je mdr. soavtor protokolov TCP in IP, pionir omreževanja. V DARPA postal kasneje direktor IPTO (Informational Processing Techniques Office), kjer je ustanovil milijardo-dolarski projekt Strategic Copmuting Initiative, največjo investicijo ameriške federalne vlade v računalništvo ever ('83 do '93) - razvijali so proizvodnjo čipov in umetne inteligence. Ustrašili so se japoncev, podobno kot v 50ih sovjetov.

Po DARPA ustanovil CNRI (corporation for national research initiatives), neprofitno organizacijo kjer je delal tudi guido van rossum (avtor pythona). Tam so izdali python verzije 1.3 do 1.6 ter GNU mailman.

Preko očeta v sorodu s fizikom Hermanom Kahnom, ki je napisal knjigo o tem kako bi amerika lahko zmagala nuklearno vojno in postal inspiracija za dr. Strangelove-a v znanem Kubrickovem filmu. Ustanovil je Hudson institut, konzervativni think tank ki je začel pri premišljevanju hladnovojnih scenarijev in se razširil na polja ekonomije, zdravstva, šolstva in gemblanja. Delal je tudi v RAND korporaciji, močnem hladnovojnem inštitutu, vpletenem v vietnamsko vojno, iraško vojno, danes pa kuri "AI apokaliptični" scenarij.

str. 77

Stoy 1977

Vaje

1.1 Kaj vrnejo izrazi?

1.2 Pretvori izraz v prefix obliko

  (/ (+ 5 4
        (- 2
           (- 3
              (+ 6
                 1/3))))
     (* 3
        (- 6 2)
        (- 2 7)))

-43/180

1.3 procedura, ki prejme 3 argumente in vrne vsoto kvadratov vecjih dveh

  (define (vsota-vecjih-kvadratov a b c)
    (cond ((<= a b c) (+ (* b b) (* c c)))
          ((<= b a c) (+ (* a a) (* c c)))
          (else (+ (* b b) (* a a)))))

  (vsota-vecjih-kvadratov 6 1 7)

85

1.4