| ||||||
| 2001/2/9-10 [Politics/Foreign] UID:20543 Activity:moderate |
2/8 Anybody tried mailing seeds outside the country? Do most countries
allow this? I'm sending some seeds to Tunisia, but I'm asking about
this in general. Thanks.
\_ I don't know about shipping seeds out of the country, but I
have received seeds from out of the country (Chile) just fine.
\_ most countries will have SERIOUS problem when they got seeds
from foreign country. The proper route is to go through
custom, and it WILL take forever. When you sending the seeds
out, I doubt U.S. is going to have problem with that, but you
better check on Tunisia.
\_ Agree that the legal way is to go through customs.
But, I would sooner just send them in a regular
envelope, and take my chances. How are you going to
contact the Tunisia plant permit people, anyway?
\_ I also received seeds just fine from the Netherlands. How
will anyone know there are seeds in there unless you're
sending enough for them to sow a whole field? --dim |
| 2001/2/9-10 [Computer/SW/Languages/Java] UID:20544 Activity:high |
2/8 can someone please recommend a beginning java book for someone
who's only programming experience is equivalent to 61a? thanks.
\_ Just Java by Van der Linden is pretty good.
\_ "Thinking In Java" is almost too verbose. like having your hand
held every step of the way. available online, for free. google.
type "thinking in java bruce"
\_ Just Java by Peter Van der Linden
\_ thank you. this is the first time i've gotten
a straight answer on the motd.
\_ so all the previous motd answers are gay? |
| 2001/2/9 [Computer/SW/OS/Solaris] UID:20545 Activity:nil |
2/8 How do I find or calculate the total number of processes a Solaris |
| 2001/2/9 [Computer/HW/Memory] UID:20546 Activity:kinda low |
2.8 box can run before running out?
\_ Run out of what? If you mean memory, there is no simple answer -
it depends on how much RAM & swap you have and how much each process
uses. -alan-
\_ 2.8 same as pre-2.8 (except ptys are dynamically alloc'd)
Examine with: sysdef -i or
# adb -k /dev/ksyms /dev/mem
parameter-name/D
^D (to exit)
or
# /etc/crash
> od -d parameter-name
> var
where parameter-name is: maxusers, maxnprocs, or maxnuprc
2.8 can do >30K processes by modifying several params(bet its buggy)
Put set pidmax=999999 in /etc/system
modify pre-2.8 formulas:
max_nprocs = ( 10 + 16 * maxusers ) ==> procs system-wide
maxuprc = ( max_nprocs - 5 ) ==> procs per user & 5 reserved
for root but can be modified.
See http://docs.sun.com for real details -- I'm just guessing. |
| 2001/2/9-11 [Computer/Theory] UID:20547 Activity:high |
2/8 I have 20 positive numbers and five desired totals (all floating point
numbers). I need to pick five mutually exclusive sets (not necessarily
exhausive) of numbers from the 20 numbers, and then sum up the numbers
in the five sets to get five totals. My goal is to minimize the
mean-of-squares of the differences between the five totals and the five
desired totals. I wrote a C program to do the brute-force try-all-
combinations method (that's (5+1)^20 combinations), and it looks like
it's going to need ~120 years of CPU time on my P-II 350MHz! Is there
any better algorithm for doing this kind of things? Thanks. -- yuen
\_ why isn't it 20!/(20-5)! ?
\_ This is known as a 'bin packing problem.' It is NP-hard (in other
words it is at least as hard as any problem in NP). -- ilyas
\_ exclusive means (20! / (5! * (20-5)!)) right?
\_ No, that would be the # of combinations to pick one set of five
numbers from the 20 numbers. But in my case I need to pick five
exclusive (ie. non-overlapping) sets instead of one, and each
set can contain anywhere from zero to 20 numbers. -- yuen
\_ Can you use an approximate solution? I think of this problem
as being more similar to integer programming. It's equivalent
to min_A ||Ax-b||^2, such that 1^T A <= 1, where x is your
vector of 20 positive numbers, b is the five desired sum, and
A is a 5x20 matrix with the entries constrained to be either
zero or 1. You won't be able to reach the exact global optimum
in poly time, but perhaps you can try adding an L_1 constraint
to the objective? i.e.
min_A ||Ax-b||^2 + lambda*sum_ij |A_ij|, s.t. 1^T A <= 1
L_1 penalty punishes any non-zero values, so A will have as
many non-zero values as possible. Of course you're still
left with the problem of deciding which entries of A to clamp
to 1... Uh, need more optimization fu. -- alice
\_ If my memory serves me right, LP relaxation isn't all that great
for bin-packing. The first reference point to check would be
_Approximation_Algorithms_For_NP-Hard_Problems_, edited by Dorit
Hochbaum:
http://www.ieor.berkeley.edu/~hochbaum/html/book-aanp.html
It should be available at any university library by now. Chapter
2, written by Coffman, Garey, and Johnson (yes, THOSE Garey and
Johnson), is "Approximation Algorithms for Bin Packing: A Survey"
-alexf
\_ I'm not up to date with NP approximation algorithms,
but LP might be the easiest (and most practical) to
implement than more complicated methods. BTW, one can
express 0/1 constraints using (2A_ij-1)^2 = 1. The
problem then is no longer LP, but you can get a lower
bound using Lagrange relaxation (i.e. switching min & max),
then use gradient descent or something on the lower bound
function, which is usually much more tame than the original
problem. This all sounds very complicated but is actually
doable. I just don't know how good the approximation is.
Maybe the book will say something about it. -- alice
\_ Thanks for all the suggestions. Understanding what you
all said is already hard enough. Gotta refresh my
170-series knowledge first before I go from here. -- yuen
\_ can you think of a useful lower bound for what you're
suggesting? you are talking about lower bounding
|Ax-b|^2 + l*(|2A-1|^2-1) right? I'd bet that your
regularization term smooths out the surface so much
that you could just solve this using gradient descent.
that you could just solve this using newton raphson.
\_ this is one smart broad. |
| 2001/2/9 [Computer/SW/Security] UID:20548 Activity:very high |
2/8 Question about ssh or need confirmation.
- purpose of using ssh is to avoid information that I read at my
terminal not being seen by someone in between the traffic, so
does that mean if my terminal is being mornitored (i.e., my employer
or network admin is watching my console at a remote terminal), they
will only see garbled messages?
- or does ssh only ensures data send between soda and my terminal not
being intercepted, but once information gets displayed on my screen,
a mornitoring agent can just capture the screen and still see every
key stroke I type in or every message I am reading?
\_ work on your fucking english
\_ hahhaha...having a hard time reading? I don't see the
others have any problem. Can you just point out one flaw
so that I can fix it.
\_ double negative, run-on sentence, fragmentary
phrase, passive voice, misspelling. And that's
just the first sentence.
\_ ssh encrypts data on the network between your host and wherever you
ssh to ( in this case, soda). If your host has been compromised
by whomever might be monitoring you, there is little ssh (or
anything else for that matter) can do to stop you from being
monitored.
\_ here's what I do at work: swap around the keycaps on my
keyboard. You should see the security people tearing their
hair out! muahhaha!
\_ how does that help really?
\_ security through obscurity. though the right way to
do this is to use a qwerty keyboard in dvorak mode.
and remove the 'W'. |
| 2001/2/9-10 [Computer/SW/Mail] UID:20549 Activity:high |
2/9 Let's say I have two UNIX accounts. Is there .forward some trick
that I can do (without the infinite loop) such that the email
received at both accounts can be accessed at either account?
\_ "man procmailex" and look for: "Suppose you have two accounts,
you use both accounts regularly, but they are in very distinct
places"
\_ you don't need procmail if both of the servers involved are
running sendmail. If your accounts are foo@bar and
baz@garply, put this in .forward on foo@bar:
\foo
\baz@garply
and this in .forward on baz@garply:
\baz
\foo@bar
Note that this may not work without sendmail, since other MTAs
may ignore backslashed email addresses on incoming mail. -alexf
\_ uh, it also will create an infinite loop. good job.
\_ This also doesn't let you filter the mail. Procmail's
solution is more general.
\_ Thanks! It works great, though some tweaking was necessary
due to some odd configuration on one of the servers (piping to
sendmail didn't work). |
| 2001/2/9-10 [Computer/SW/Unix] UID:20550 Activity:low |
2/8 Do you use RXVT instead of xterm? You should. -ali
\_ RXVT- that's almost like RSVP. you know like 10. Spatz's.
\_ Why? I actually use tektronix mode and like xterm's configuration
a little better (e.g. bold actually works by default)
\_ i think you're cool for using tektronix mode, whoever you are.
i just checked this bold thing. it works fine for me. what's
the problem exactly? -ali
\_ no problem. I may agree with your logic, but I simply
don't like your condescending tone and I don't like you.
\_ that's fine. my superior ability to love transcends your
petty feelings. use rxvt. -ali |
| 2001/2/9-10 [Computer/SW/OS/FreeBSD] UID:20551 Activity:moderate |
2/9 I'm Trying to add sound to FreeBSD 4.2- the handbook says that
I have to check /dev/sndstat after recompiling and rebooting for
FreeBSD Audio Driver (newpcm) Sep 21 2000 18:29:53
Installed devices:
pcm0: <Aureal Vortex 8830> at memory 0xfeb40000 irq 5 (4p/1r +channels duplex)
/dev/sndstat doesn't exist, but the pcm0 ID does show up in dmesg.
man pages for sndstat are nil, what do I do?
\_ cd /dev && ./MAKEDEV snd0
\_ Thanks, I just skipped ahead and did that. Now how do I mount a
CDROM drive full of mp3s?
\_ mkdir /mnt/cd && mount /dev/acd0c /mnt/cd
\ I got an incorrect superblock doing that.
mount_cd9660 /dev/acd0c /mnt/cd did work though. Thx
\_ mount -t cd9660 blahblahblah |
| 2001/2/9-11 [Computer/SW/Languages, Computer/SW/Unix] UID:20552 Activity:nil |
2/9 How do you do multilevel command substitution? For example,
echo `echo `echo `echo hello```
But how do you escape the `?
Also how do you print ' within ', without using "? For example,
echo ' \' ' (escape doesn't work)
\_ In sh (or ksh or bash), echo $(echo $(echo hello)). In any
shell, echo 'here'\''s how' |
| 2001/2/9-10 [Recreation/Dating] UID:20553 Activity:very high |
2/9 I know a 25-year old female EE grad student from China, who
wears a red ring on her left-hand ring finger. What does this
mean?
\_ it means she is married to a Triad leader and has a wide
variety of superpowers.
\_ why not ask her and find out!
\_ because he's a pussy!
\_ that's too obvious and makes too much sense. try again.
\_ It means she's married. The red color is probably just for fashion
and has no special meaning. But let us know after you ask her.
Is she hot? Pics?
and has no special meaning.
\_ Of course, she could just be wearing it to discourage clueless,
desperate geeks from hitting on her all the time. A friend of
mine who worked as a waitress at a cocktail bar did that all the
time.
mine who worked as a waitress at a cocktail bar used that ploy.
\_ Geek ward?
\_ Pics?
\_ No Pics for you! |
| 2001/2/9-10 [Computer/SW/Security] UID:20554 Activity:nil |
2/9 ssh has vunerability. Integer overflow. Openssh is safe.
\_ Take that, Tom! Take that, Bowlarama! Take that, Convenience
Mart! Take that, Nuclear Power Plan--oh, fiddlesticks.
\_ Bowlarama! Good times! |
| 2001/2/9-10 [Politics/Domestic/President/Clinton] UID:20555 Activity:moderate |
2/9 I keep hearing "Bush retreats to his ranch." What is that like, a
mansion or somethin'? How come Clinton never retreats to his ranch
or penthouse (possibly with interns)?
\_ Clinton retreated to the oral^H^H^Hval office
\_ That is so incredibly stupid it's making my eyes bleed.
\_ Watch a western sometime, cowboy, and then you'll understand.
\_ Is this a "Silverado" or a "Josey Wales" kinda retreat?
\_ It's a "daddy, what do I do now?" sort of retreat. |
| 5/17 |