| 1. ProductShot AI |
| Published: 2026-09-29 [Tue] 16:18, by |
| ProductShot AI — https://productshotai.app/ — Evan Reed |
| 22. Excercise 1.8 |
| Published: 2026-09-14 [Mon] 14:41, by |
|
>>4 This one was just implementing the formula and then replacing the old one in the "improve" procedure (define (improve guess x) (/ (+ (/ x (square guess)) (* guess 2)) 3) |
| 21. PHATCATTTT |
| Published: 2026-09-14 [Mon] 02:07, by |
|
>>19 the tolerance I specified was kinda wide, which made the big number calculation off by a good amount (oops!). After reducing the tolerance to 0.000000000001 (rest of the code kept the same) i get the same result as my calculator (Casio fx-991EX). Dr racket seems to have rounded the small square roots output to 1e-7, im not sure if this is a fault in my code or just computer stuff (can anyone confirm?) also i noticed that if im just comparing the guesses,i dont need to square them and then divide. I also had redundant (abs ) functions in the code so heres an improvement (define (good-enough? guess x) (< (abs (- (/ guess (improve guess x)) 1)) 0.000000000001)) (sqrt 0.00000000000001) ;very small number test (sqrt 1000000000000000) ;very large number test outputs: 1e-7 31622776.601683907 |
| 20. |
| Published: 2026-09-14 [Mon] 01:53, by |
|
>>19 where 0.001 was the tolerance to see if the guess was good enough |
| 19. Excercise 1.7 |
| Published: 2026-09-14 [Mon] 01:50, by |
|
>>4 The full code is VERY long and has multiple things needing to be defined so ill only post what was changed from the procedure defined in SICP. My thought process was: need to compare guesses, so need to know guess-1 and guess-2 modify the improve definition to "save" the old guess? (oh no...) OR just use (improve guess x) itself as the guess 2 then ;modified from 1.1.7 for Exercise 1.7 (define (good-enough? guess x) ;(< (abs (- (square guess) x)) 0.001));old/original code [from SICP] (< ;check if guess is within tolerance (abs ; stops it from breaking if it gives a negative number (- ;small difference between subsequent guesses => fraction ~1, so fraction-1 ~0 (/ (abs (square guess)) (abs (square (improve guess x)))) 1)) 0.001)) ... (sqrt 0.00000000000001) ;very small number test (sqrt 1000000000000000) ;very large number test answers were correct |
| 11. HomePage revision |
| Published: 2026-09-13 [Sun] 16:35, by |
|
---- **Special pages:** [All Pages](/w/all) , [Recent Changes](/w/recent) , [Popularity](/w/popular), [Random](/w/random), [Atom feed](/feed.atom) ---- Welcome to WikiWikiWiki, an [open source](https://github.com/153/wikiwikiwiki/) project sponsored by the GikoPoi community. We are the original c2 WikiWiki [[cloan]] for the VipQuality community, being a continuation of 4x13's ThisWiki. This is meant to be a wiki that can be edited by nearly anyone who wants to, with little to no friction! The tone is meant to be informal. After solving the CAPTCHA, check out the MarkUp guide, and then have at it. Please keep in mind that WikiWikiWiki is NOT a WikiWiki'Wiki. Go to [Meatball Wiki](http://meatballwiki.org/wiki/) if you are into that kind of thing. We are something more like TanasinnWiki back in its glory days. Wiki discussion: [Pohon BBS](https://bbs.gikopoi.com/tags/wiki/) Advice for writing: WritingPhilosophy |
| 18. exercise 1.3 |
| Published: 2026-09-09 [Wed] 20:55, by |
|
>>4 [(define (square a) (* a a)) (define (smallest x y z) (if (< x y) (if (< x z) x z) (if (< y z) y z))) (define (procedure x y z) (- (+ (square x)(square y)(square z))(square (smallest x y z)))) (procedure 7 10 10)] |
| 17. epic phail |
| Published: 2026-09-09 [Wed] 15:35, by |
|
>>16 Fixed the fix #lang sicp (define (square x) (* x x)) (define (sicp_ex_1.3 x y z) (+ (if (= x y z) 0 (if (< x y) (if (< x z) 0 (square x)) (square x)))) (if (< y x) (if (< y z) 0 (square y)) (square y)) (if (< z y) (if (< z x) 0 (square z)) (square z))) (sicp_ex_1.3 1 2 3) (sicp_ex_1.3 2 2 2) (sicp_ex_1.3 2 1 0) |
| 16. fix ex 1.3 |
| Published: 2026-09-09 [Wed] 15:27, by |
|
>>14 summed all 3 squares if x y z were the same. added a check to just force one variable to zero if all the numbers were equal so theres probably a more elegant solution :P. Code: #lang sicp (define (square x) (* x x)) (define (sicp_ex_1.3 x y z) (+ (if (= x y) 0 (if (= x z) 0 (if (< x y) (if (< x z) 0 (square x)) (square x)))) (if (< y x) (if (< y z) 0 (square y)) (square y)) (if (< z y) (if (< z x) 0 (square z)) (square z)))) (sicp_ex_1.3 1 2 3) (sicp_ex_1.3 2 2 2) (sicp_ex_1.3 2 1 0) |
| 49. Spoiler hack (temporary) |
| Published: 2026-09-09 [Wed] 05:15, by |
|
I am too lazy to make a proper "spoiler field" (similar to markdown's code fences) to spoiler-ify multiple lines of text right this second, so if you need to make an entire post a spoiler post, do it exactly like this: %%% The text you want to hide across multiple lines -- the entire body of a post %%% That's 3 %'s at the very start of a post, immediately press enter to break the line, everything else, enter, 3 %'s again with nothing following. Later I'll probably just add a [ ] Spoiler checkbox but I've been up for something like 30 hours and now is not the time for that. Be patient! enjoy and use responsibly! |
| 14. Excercise 1.3 |
| Published: 2026-09-09 [Wed] 01:43, by |
|
>>13 My attempt at exercise 1.3. it took me a long time as most of my attempts made code that excluded anything that wasn't the maximum number, so i guess finding the "middle" number is what makes this challenging. my first attempts were checking each variable against the others individually (mistake). if x>y then output x otherwise 0, if x>z output x otherwise 0 then multiply both outputs, repeat for each variable (rather silly in retrospect). After this i decided to only compare to the third variable if the first check failed and directly compute the square if the variable wasn't the minimum. Code below: #lang sicp (define (sicp_ex_1.3 x y z) (+ (if (< x y) (if (< x z) 0 (* x x)) (* x x)) (if (< y x) (if (< y z) 0 (* y y)) (* y y)) (if (< z y) (if (< z x) 0 (* z z)) (* z z)))) (sicp_ex_1.3 1 2 3) result was 13 so it worked |
| 12. |
| Published: 2026-09-08 [Tue] 20:11, by |
|
>>3 Famous article by a guy who used Lisp to become a billionaire : > Graham, Paul. "The Roots of Lisp." (2001) 15pp https://wiki.eecs.yorku.ca/course_archive/2014-15/W/6339/_media/jmc.pdf discusses how 7 primitives became the meta language |
| 10. outputs color based on stats (hopefully) |
| Published: 2026-09-08 [Tue] 19:37, by |
|
>>3 (define (clouds_color strength intelligence Defense) (define red strength) (define blue intelligence) (define green defence) (list red green blue))) % gives RGB color (idk how to/ if its even possible for lisp to output a color) |
| 9. Chapter 5 |
| Published: 2026-09-08 [Tue] 19:30, by |
|
> Computing with Register Machines https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-30.html#%_chap_5 |
| 8. Chapter 4 |
| Published: 2026-09-08 [Tue] 19:29, by |
|
> Metalinguistic Abstraction https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-25.html#%_chap_4 |
| 7. Chapter 3 |
| Published: 2026-09-08 [Tue] 19:28, by |
|
> Modularity, Objects, and State https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-19.html#%_chap_3 |
| 6. Chapter 2 |
| Published: 2026-09-08 [Tue] 19:27, by |
|
> Building Abstractions with Data https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-13.html#%_chap_2 |
| 5. phatcat power level formula (first scheme test) |
| Published: 2026-09-08 [Tue] 19:24, by |
|
>>3 (define phatcat_powerlevel 1200) (define unlocked_potential 500) (define (phatcat_bulky_transformation x y) (* 1.2 (+ x y))) (phatcat_bulky_transformation phatcat_powerlevel unlocked_potential) |
| 4. Chapter 1 |
| Published: 2026-09-08 [Tue] 19:21, by |
|
SICP chapter 1 > Building Abstractions with Procedures https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-9.html#%_chap_1 |
| 3. |
| Published: 2026-09-08 [Tue] 19:20, by |
|
Random Scheme / Lisp / programming discussion that doesn't fit into chapter discussion goes here.... |
| 2. |
| Published: 2026-09-08 [Tue] 19:19, by |
|
General Scheme troubleshooting / installation help / etc goes under this comment.... |
| 1. SICP : Let's Read! |
| Published: 2026-09-08 [Tue] 19:18, by |
|
> SICP Book: https://mitp-content-server.mit.edu/books/content/sectbyfn/books_pres_0/6515/sicp.zip/full-text/book/book-Z-H-4.html > SICP Lectures: https://www.youtube.com/playlist?list=PLE18841CABEA24090 > Racket Scheme https://racket-lang.org/download/ > SICP Racket https://docs.racket-lang.org/sicp-manual/Installation.html Let's embrace the tree structure of Pohon BBS. Top level comments for chapters of the book, replies to top level comments for discussions of the chapter. Comment #2 will be for general help installing Scheme Comment #3 will be for random Scheme discussion that doesn't fit into chapter discussion. Ready, start, go! |
| 1. A man has fallen into BAD END in sea city! |
| Published: 2026-07-28 [Tue] 10:40, by |
| @Admin today i was just going about my day peacefully sending GOATSE to soyteens when some (handsome) dark boon joined with the name BANNER and proceeded to call me a nerd and ban me! As CEO of giko, it is your responsibility to do something about this ASAP. I've already received many phone calls from concerned sea citizens, many of which are refusing to leave their homes while this hit and run banner roams the streets freely! |
| 6. |
| Published: 2026-07-27 [Mon] 16:12, by |
| Movie theater!!! |