2009 Sep 14 00:08:48  <inimino> hey aamar
2009 Sep 14 00:09:19  <aamar> hey inimino
2009 Sep 14 00:09:44  <aamar> how's it going?
2009 Sep 14 00:09:52  <inimino> good :)
2009 Sep 14 00:09:56  <inimino> this chapter is fun, but slow going for me
2009 Sep 14 00:10:26  <aamar> same here
2009 Sep 14 00:10:42  <aamar> took longer than planned -- got to 3.71
2009 Sep 14 00:10:50  <inimino> I got to 3.70 :)
2009 Sep 14 00:11:23  <inimino> 3.66 took some time
2009 Sep 14 00:12:21  <aamar> yes
2009 Sep 14 00:12:33  <aamar> cool
2009 Sep 14 00:12:40  <aamar> should we start on 3.63 ?
2009 Sep 14 00:12:48  <inimino> ok
2009 Sep 14 00:13:12  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.63
2009 Sep 14 00:14:58  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1188-1192
2009 Sep 14 00:16:02  <aamar> okay, the same answer
2009 Sep 14 00:16:37  <inimino> ok
2009 Sep 14 00:16:51  <aamar> 3.64 ?
2009 Sep 14 00:17:05  <inimino> that page hasn't loaded yet
2009 Sep 14 00:17:15  <aamar> :( github
2009 Sep 14 00:17:17  -*- inimino hits refresh
2009 Sep 14 00:17:31  <inimino> it's coming in now
2009 Sep 14 00:17:41  <aamar> ok, sorry for the long file as well
2009 Sep 14 00:17:50  <aamar> could split it up if it causes problems
2009 Sep 14 00:18:07  <inimino> ok, yeah, same answer
2009 Sep 14 00:18:16  <inimino> now that it's loaded we should be good
2009 Sep 14 00:18:25  <inimino> alright, 3.64
2009 Sep 14 00:18:37  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.64
2009 Sep 14 00:20:19  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1194-1215
2009 Sep 14 00:20:24  <aamar> or you can just scroll down, of course
2009 Sep 14 00:20:33  <aamar> same answer here
2009 Sep 14 00:20:37  <inimino> yeah same
2009 Sep 14 00:20:45  <inimino> I used cond for whatever reason
2009 Sep 14 00:21:00  <inimino> ok, 3.65?
2009 Sep 14 00:22:49  <aamar> ok
2009 Sep 14 00:22:56  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.65
2009 Sep 14 00:23:15  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1217-1244
2009 Sep 14 00:23:29  <aamar> interesting, different answers...
2009 Sep 14 00:24:56  <aamar> actually not that different
2009 Sep 14 00:25:05  <inimino> different way of alternating the signs
2009 Sep 14 00:26:18  <inimino> looks very similar
2009 Sep 14 00:27:15  <aamar> terms in my first pass look a little different than yours, checking...
2009 Sep 14 00:29:02  <aamar> ok, they're exactly the same, I just went to the 9th element
2009 Sep 14 00:29:11  <aamar> okay, all the rest look the same too
2009 Sep 14 00:29:45  <inimino> ok
2009 Sep 14 00:30:02  <inimino> alright, 3.66?
2009 Sep 14 00:30:51  <aamar> yes
2009 Sep 14 00:30:58  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1246-1259
2009 Sep 14 00:31:21  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.66
2009 Sep 14 00:34:05  <aamar> interesting, after all that our derivation is very similar
2009 Sep 14 00:35:43  <aamar> and we get the same results
2009 Sep 14 00:36:13  <inimino> yes, looks the same
2009 Sep 14 00:36:51  <inimino> I ended up looking at examples to solve this one also
2009 Sep 14 00:38:38  <aamar> Yes, had an idea that there would be some 2^m factors, but getting beyond that took writing a few of them out.
2009 Sep 14 00:38:51  <aamar> Okay, 3.67 ?
2009 Sep 14 00:38:59  <inimino> ok
2009 Sep 14 00:39:23  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.67
2009 Sep 14 00:39:59  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1261-1279
2009 Sep 14 00:40:52  <inimino> looks similar
2009 Sep 14 00:40:58  <inimino> different ways of interleaving the results
2009 Sep 14 00:41:23  <aamar> awesome: interleave-3
2009 Sep 14 00:41:28  <aamar> One minor thing
2009 Sep 14 00:42:03  <aamar> in the second stream-map in all-pairs, I think the list should always put the element from s first.
2009 Sep 14 00:42:43  <inimino> oh
2009 Sep 14 00:43:32  <inimino> you're right
2009 Sep 14 00:44:26  <inimino> ok, fixed
2009 Sep 14 00:44:34  <inimino>      (stream-map (lambda (x) (list x (stream-car t)))
2009 Sep 14 00:44:34  <inimino>                  (stream-cdr s))
2009 Sep 14 00:45:06  <aamar> right ok
2009 Sep 14 00:45:09  <aamar> 3.68 ?
2009 Sep 14 00:45:12  <inimino> ok
2009 Sep 14 00:45:22  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.68
2009 Sep 14 00:45:23  <aamar> ha, I never went back and wrote out a proper answer!
2009 Sep 14 00:45:58  <aamar> Yours looks right.
2009 Sep 14 00:46:03  <inimino> hehe, ok
2009 Sep 14 00:46:12  <inimino> I guess I could have mentioned 'delay' in there somewhere
2009 Sep 14 00:47:00  <inimino> 3.69?
2009 Sep 14 00:48:06  <aamar> ok
2009 Sep 14 00:48:24  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1284-1308
2009 Sep 14 00:48:41  <inimino> http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.69
2009 Sep 14 00:50:19  <inimino> looks like a put a 't' in place of 'u'
2009 Sep 14 00:50:23  <inimino> fixing...
2009 Sep 14 00:50:29  <aamar> yes, just saw that
2009 Sep 14 00:50:55  <aamar> interleave-3 makes it a lot cleaner
2009 Sep 14 00:51:05  <inimino> fixed
2009 Sep 14 00:51:27  <inimino> well, it saves a line anyway ;)
2009 Sep 14 00:51:31  <aamar> otherwise, look the same, right?
2009 Sep 14 00:51:37  <inimino> apart from that, yep looks the same
2009 Sep 14 00:52:04  <aamar> 3.70 took a while
2009 Sep 14 00:52:14  <aamar> surprisingly
2009 Sep 14 00:53:00  <inimino> yeah, I only finished a) so far but it is here: http://inimino.org/~inimino/projects/2009/SICP/chap_3/3.70
2009 Sep 14 00:53:15  <aamar> http://github.com/aalearn/aalearn-sicp/blob/7c1b0675df54c90856b16b25ad740539b64e659e/ch3-outline.scm#L1309-1353
2009 Sep 14 00:53:30  <inimino> b) looks like it could be involved
2009 Sep 14 00:54:18  <aamar> had the most trouble just getting merge-weighted to work
2009 Sep 14 00:55:08  <inimino> s1car and s2car clean things up a bit, I think I'll copy those
2009 Sep 14 00:55:30  <aamar> one thing is -- this only becomes clear later -- it seems that sicp wants you to not eliminate duplicate items
2009 Sep 14 00:56:39  <inimino> oh, interesting
2009 Sep 14 00:56:44  <inimino> I wondered about that
2009 Sep 14 00:56:55  <inimino> but it seemed like it might be useful so I did it
2009 Sep 14 00:56:56  <aamar> yes -- see 3.71
2009 Sep 14 00:57:00  <inimino> ok
2009 Sep 14 00:57:36  <inimino> ah yes
2009 Sep 14 00:58:04  <inimino> of course it is not necessarily the case that the weighting function gives different pairs different weights
2009 Sep 14 00:58:09  <inimino> actually...
2009 Sep 14 00:58:18  <inimino> that won't even work for the sums
2009 Sep 14 00:59:20  <aamar> oh right, good point
2009 Sep 14 00:59:26  -*- inimino fixes
2009 Sep 14 00:59:47  <inimino> well, these are fun ones
2009 Sep 14 01:00:30  <inimino> I'm glad we are out of the banking examples and back into more mathsy stuff :)
2009 Sep 14 01:01:44  <inimino> ok, my 3.70 is fixed
2009 Sep 14 01:02:30  <aamar> cool, and weighted-pairs matches to the character
2009 Sep 14 01:02:56  <inimino> uncanny :)
2009 Sep 14 01:03:52  <aamar> ok, what should we do next?
2009 Sep 14 01:03:57  <aamar> finish out ch. 3?
2009 Sep 14 01:04:23  <aamar> 3.82
2009 Sep 14 01:04:26  <aamar> that's not that much
2009 Sep 14 01:04:42  <inimino> yeah, was just looking ahead
2009 Sep 14 01:04:50  <inimino> sounds good, let's finish it up
2009 Sep 14 01:05:14  <aamar> ok cool
2009 Sep 14 01:05:31  <aamar> liking 3.5 a lot, also looking forward to ch. 4
2009 Sep 14 01:05:37  <inimino> me too :)
2009 Sep 14 01:06:17  <aamar> ok, let's wrap up ch. 3 in 2 weeks.
2009 Sep 14 01:06:25  <inimino> alright, the 27th
2009 Sep 14 01:06:34  <inimino> see you then!
2009 Sep 14 01:06:38  <aamar> cool, see you then