On 22/01/14 15:51, waldo kitty wrote: > On 1/22/2014 3:52 AM, Lukasz Sokol wrote: > [...] >> ^and this... >> looks like a (good?) use for a dynamic array of TMinMaxState = [mmNone, >> mmMin, mmMinMax, mmMax]; >> (then var Options = array[static or dynamic] of TMinMaxState;) >> >> This assumes options have a fixed position in the array however... but the >> bitwise code was >> assuming this anyway. > > ok so basically converting 16 bits storage into an array? currently > only 15 bits are being used and i don't know that any more will be > added... but i'm not seeing how to add (logical AND) them together > for > > optionA:mmMin AND optionC:mmMinMax > > and similar up to all five basic ones as > > A:mmMin AND B:mmMax AND C:mmMinMax AND D:mmMax AND E:mmMin > >> And yes, 4 states - one of them being mmNone - for the case when you don't >> want to use certain option.
If you insist on using bits.... define them: const OptionAmmMin = $0001; OptionAmmMinMax = $0002; OptionAmmMax = $0004; // and so on then do if Options and (OptionAmmMin and ... ) then ? I would have thought, that having an array of TOption like I wrote, would ensure the exclusivity. And having the array dynamic, you can check for its size, then write some clever code to use it ;) > > yes, i've basically been ignoring mmNone because all the bits are off so we > just skip over it in the ANDing code > >> If there is a lot of options, but not always consecutive - so there would be >> a lot more of mmNone's >> than significant states (IOW the data is sparse) - > > yes, with what i have done, there are 1023 valid combination... 1024 > if we count all options off (or mmNone)... that's out of 32767 > combinations where the majority are invalid... it is no wonder, with > 1023 combinations, that i got lost/confused with my first attempt > using if/then/else and while trying to manually implement the bitmap > CASE code... If you count permutations (so combinations not repeating) you'd have 120 valid ones...? http://easycalculation.com/statistics/permutation-combination.php do I understand that correctly? >> maybe do >> >> TOption = record >> Index : [whatever type would suffice here]; >> State : TMinMaxState; // [which could then be 3 state not 4] >> end; >> >> and use a dynamic array to hold the TOption(s). > > as above, i'm not seeing how to AND each valid set together for later use in > the filtering code :? > >> Excuse my lameness please :) as I am not a programmer by trade. > > no problems... i'm looking for ideas and input for handling items like > this... i appreciate any input on this... > > it would seem that things like this would come up a lot and that > there would already be a class or possibly an object that one could > feed the settings array to with the options that hold each array and > then to be able to walk thru like one can do with TStringsList > > eg: fooList:TStringsList; > [...] > fooList[i]:='blah'; > [...] > writeln(fooList[i]); > > i actually did look at the TBits class but didn't see an easy way of > walking it like one can do with TStringsList... my finding and > looking at TBits was after some 12+ hours of manually coding > if/then/else, getting lost in the details and starting over numerous > times... > > what i finally did with my current attempt using a bitmapped word was > to write a tool to generate all the code for the case statement... > with this i was able to > 1] find out how many valid combinations there are (1023) > 2] have the ANDs all written in the proper order for each valid bitmask > 3] generate a file that is easily included {$I bitcase.inc} > > any changes to the ordering need only a small rewrite to the > generating tool to create the new CASE code for the filter... the > resulting include file is only (!) 392353 bytes at 7932 lines with no > comment lines... that's ~3x the size of the program's .pas file of > 119151 bytes at 3157 lines with a few hundred comment lines... > > this current implementation is used for output filtering... there's > going to be an exact duplicate used for input selection with the only > difference between the two CASE code blocks being the routine called > on a match... > eg: > case FilterBits of > 0 : writeoutput; > 1 : begin > if (rec^.optionA >= optionA_min) and (rec^.optionA <= optionA_max) > then > writeoutput; > end; > 2 : begin > if (rec^.optionA >= optionA_min) then > writeoutput; > end; > 3 : begin {invalid} end; > 4 : begin > if (rec^.optionA >= optionA_max) then > writeoutput; > end; > [...] > > > case SelectBits of > 0 : addItem; > 1 : begin > if (rec^.optionA >= optionA_min) and (rec^.optionA <= optionA_max) > then > addItem; > end; > 2 : begin > if (rec^.optionA >= optionA_min) then > addItem; > end; > 3 : begin {invalid} end; > 4 : begin > if (rec^.optionA >= optionA_max) then > addItem; > end; > [...] > > i think i should be able to use one routine for both input selection > and output filtering... done by pass the bitmap and the routine to be > used... that'll save having to worry about editing in more than one > place when things change... i just gotta figure out how to pass the > routine to use...> > would something like: > > procedure runCase(var bitMap:word; whichProcedure: pointer); > > called with > > runCase(SelectBits,@addItem); > > runCase(FilterBits,@writeoutput); > > be the way to do this?? > > sometimes my linear procedural mind really gets in the way :/ > Huh, well a lot of micro-management goes on here; What if you did it like: - define the valid bit masks (permutations?) at the start, dynamically - associate the procedures (their pointers) to jump to with the valid bit masks in a new data type (- do you REALLY have that many procedures ? Or are they somewhat repeating themselves ?) - then just walk the array of [bit mask, proc pointer] records and jump to pointers supplied if matching? No ifs, no buts, treat the Options as a bitmask if such is its purpose? Just a thought, -L. _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
