World: r3wp
[!REBOL3-OLD1]
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Sunanda 2-Nov-2009 [19381] | It can be easier to read if you have: system/options/binary-base: 16 bits: make bitset! "abc" == make bitset! #{00000000000000000000000070} |
Pekr 2-Nov-2009 [19382x3] | Why 'remove requires /part refinement? I have never seen function to be pushed to use refinement by default: |
otoh bitset probably does not have seriea-like "current position", so it might be questionable, what single remove bitset should do .... | |
I never programmed in assembler, so I am not quite strong with all those binary things. Could someone explain to me, how are bitsets done in low level? E.g.: >> bits: make bitset! 1 == make bitset! #{00} >> find bits 1 == none >> append bits 1 == make bitset! #{40} >> find bits 1 == true What does the binary #{40} = integer 64 mean? How is this value constructed? | |
Geomol 2-Nov-2009 [19385] | You created a bitset of just one byte. When you append 1 to the bitset, you set the bit representing position 1 in the bitset, so you get #{40}, which is equal to binary: 2#{01000000} Position 0 in the bitset is the first bit. Example: >> bits: append make bitset! 1 0 == make bitset! #{80} which is equal to binary: 2#{10000000} Note that bitsets have changed in R3! |
Pekr 2-Nov-2009 [19386] | Precision delta time measurements - http://www.rebol.net/r3blogs/0289.html |
Pavel 2-Nov-2009 [19387] | Have Bitset! some limit? May it be used as bitmap index for some larger set? |
Geomol 2-Nov-2009 [19388] | Bitset Virtual Length: http://rebol.com/r3/docs/datatypes/bitset.html#section-28 I read it, as if bitsets can be as long as you need, but try it out. More information about bitsets, including details of changes from R2 to R3: http://www.rebol.net/wiki/Bitsets |
kcollins 2-Nov-2009 [19389] | >> make bitset! to-integer power 2 24 ** Script error: invalid argument: 16777216 ** Where: make ** Near: make bitset! to-integer power 2 24 >> make bitset! to-integer (power 2 24) - 1 == make bitset! #{ 00000000000000000000000... >> |
Maxim 3-Nov-2009 [19390] | do you really need a 16MB bitset !! ? |
kcollins 3-Nov-2009 [19391] | no, but that seems to be the limit |
Pavel 3-Nov-2009 [19392] | Thanks for analysis Kcollins! Maxim the question was if Bitmap may be used as searchable bitmap index into dataset (key-value, index-value in this case) all this in searching of holly grail what is named RIF in Rebol :). The answer is yes if you would use max 16 M of indexes. The merit is using somehow compressed format. Oher info in Wikipedia bitmap indexes, or Fastbit database (database for very large datasets from particle colliders). |
Maxim 3-Nov-2009 [19393x2] | neat. |
the R3 bitset object is really nice. | |
Graham 3-Nov-2009 [19395] | Would it just be clutter to add a synonym for 'not ... eg. 'no ? |
Maxim 3-Nov-2009 [19396] | 'NO is already used for 'FALSE as in yes/no. |
Graham 3-Nov-2009 [19397] | ok. |
Henrik 4-Nov-2009 [19398] | Host builds plan: http://www.rebol.net/wiki/Host-Builds |
Maxim 4-Nov-2009 [19399] | so Carl, seems it was a bit more work than expected to get that host code out of your disk ;-) (reffering to this http://www.rebol.net/wiki/Host-Builds) |
Tomc 5-Nov-2009 [19400x2] | would someone please run his in r3 and let me know the result |
mod (power 2 63 - 3) 10 | |
Maxim 5-Nov-2009 [19402x2] | >> mod (power 2 63 - 3) 10 == -4.0 |
(in A94) | |
Henrik 5-Nov-2009 [19404] | -4.0 in OSX A94. |
Maxim 5-Nov-2009 [19405] | mine was on XP |
Sunanda 5-Nov-2009 [19406] | -4.0 .....A94, Windows Vista |
Tomc 5-Nov-2009 [19407x5] | hmmm ...should not underflow and underflow should be reported. |
it is the same back in r2 on solais & windows | |
2^48 is as high as I can go on a 32 bit windows intel before abundant underflows and only 2^ 49 on a 64 bit solaris sparc . Does R3 use the entire width of the available processor? | |
I realize these are decimal aproximations (at least on the 32 bit machine) but rebols mod function returns decimals for example mod (PI + 50.0) 10 . why would these aproximated large values not come back as their nearest decimal aproximations if t | |
.. if that is the problem | |
Maxim 5-Nov-2009 [19412] | is this a common IEEE floating point issue? |
Tomc 5-Nov-2009 [19413] | I could see that being the case on a 32 bit machine but not one with an exact representation |
Maxim 5-Nov-2009 [19414x2] | you should create a curecode ticket and discuss this with Carl. AFAIK he is savy about this stuff, so you could help him improve this if at all possible :-) |
he takes curecode VERY seriously. and it will act as a databank of info however this turns out, for future reference. | |
Tomc 5-Nov-2009 [19416] | standard significand for iEEE single precision is 24 bits so yes it is likely related to double precision behavior |
Geomol 5-Nov-2009 [19417] | I haven't got time to dig in deeper right now, but remember, there are many MOD functions: MOD, REMAINDER, MODULO, // Other? |
Tomc 5-Nov-2009 [19418x2] | origanally there was just mod I may have assumed the rest were alias' |
modulo is a wrapper around mod to make the result pretty in some cases | |
Pekr 5-Nov-2009 [19420] | by re-reading some of Max ideas about draw, View, etc., I now think that deeper change is needed. Gobs sound so old-school by his propositions .... |
Mchean 5-Nov-2009 [19421] | anyone got a rebol 3 icon for the desktop? |
Pekr 5-Nov-2009 [19422] | not yet ... |
Mchean 5-Nov-2009 [19423x2] | yeah, it's not a priority, but i moved the shortcut to my desktop |
so... :) | |
Pekr 5-Nov-2009 [19425] | some ideas from hostilefork - http://hostilefork.com/shared/rebol/rebol_rebooted_3d.png |
Henrik 5-Nov-2009 [19426] | http://www.rebol.com/consulting.html |
amacleod 5-Nov-2009 [19427] | Wher does he find the time? |
Maxim 5-Nov-2009 [19428] | maybe its the return of REBOL as a team instead of a one man show? like its used to be in the golden days of rebol 1.x ahh Bo, was such a cool guy at support :-D |
BrianH 6-Nov-2009 [19429x2] | Maxim, did you notice the link Henrik posted? The days of the one man show are over :) |
Sorry, you were commenting on the link :) Yes, it's the return of the team. | |
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