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Simplex Algorithm
11-19-2023, 04:58 PM
Post: #29
RE: Simplex Algorithm
(11-19-2023 07:05 AM)ftneek Wrote:  I agree, with only 1 pivot changing each iteration we can save a lot of operations. But I think in the beginning it still needs to go over each pivot at least once, and then the rest of the time it can pivot as you suggest.

I am not convinced that -1 slack variable will cause problem.
This was previous code, pivot only the art variables (assumed always 1's)
Code:
IF art THEN
 a:=extend(a,matrix(1,v+1));
 FOR J FROM v-art+1 TO v DO
  a[0] -= a[POS(b0,J)];
  a[0][J] := 0;
 END;
END;

But, on the safe side, it now go over all pivots.
Code:
IF art THEN a:=append(a,art_row(v,art)) END
FOR I FROM 1 to len(b0) DO a:=pivot1(a,I,b0[I]) END

Quote:I will just say I probably prefer artificial variables to be set up outside of simplex_core.
It can't be done inside of simplex?

If you prefer art row added from simplex() side, just move "IF art THEN ... END" there.
I personally like core to take care of this details. It allow the same matrix to be used for both.

simplex(m, [art=0]) ≡ simplex_core(m, pivots, variables, art, 0)

If user doesn't like simplex picked pivots, just use the core with custom pivots.
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Messages In This Thread
Simplex Algorithm - ftneek - 11-11-2023, 11:21 PM
RE: Simplex Algorithm - Albert Chan - 11-11-2023, 11:51 PM
RE: Simplex Algorithm - Albert Chan - 11-12-2023, 12:38 AM
RE: Simplex Algorithm - Albert Chan - 11-12-2023, 05:11 PM
RE: Simplex Algorithm - ftneek - 11-12-2023, 05:40 PM
RE: Simplex Algorithm - Albert Chan - 11-13-2023, 02:48 PM
RE: Simplex Algorithm - ftneek - 11-12-2023, 12:00 AM
RE: Simplex Algorithm - ftneek - 11-12-2023, 01:44 AM
RE: Simplex Algorithm - Albert Chan - 11-12-2023, 11:04 PM
RE: Simplex Algorithm - ftneek - 11-13-2023, 01:51 AM
RE: Simplex Algorithm - Albert Chan - 11-12-2023, 08:46 PM
RE: Simplex Algorithm - ftneek - 11-12-2023, 10:09 PM
RE: Simplex Algorithm - ftneek - 11-13-2023, 05:34 PM
RE: Simplex Algorithm - Albert Chan - 11-13-2023, 10:46 PM
RE: Simplex Algorithm - Albert Chan - 11-14-2023, 02:25 AM
RE: Simplex Algorithm - ftneek - 11-14-2023, 06:24 AM
RE: Simplex Algorithm - Albert Chan - 11-14-2023, 09:23 AM
RE: Simplex Algorithm - ftneek - 11-14-2023, 10:39 AM
RE: Simplex Algorithm - Albert Chan - 11-15-2023, 04:36 PM
RE: Simplex Algorithm - ftneek - 11-15-2023, 05:58 PM
RE: Simplex Algorithm - Albert Chan - 11-16-2023, 11:42 AM
RE: Simplex Algorithm - Albert Chan - 11-16-2023, 07:15 PM
RE: Simplex Algorithm - ftneek - 11-17-2023, 07:47 AM
RE: Simplex Algorithm - Albert Chan - 11-17-2023, 11:04 AM
RE: Simplex Algorithm - ftneek - 11-18-2023, 01:27 AM
RE: Simplex Algorithm - ftneek - 11-18-2023, 10:31 PM
RE: Simplex Algorithm - Albert Chan - 11-19-2023, 12:57 AM
RE: Simplex Algorithm - ftneek - 11-19-2023, 07:05 AM
RE: Simplex Algorithm - Albert Chan - 11-19-2023 04:58 PM
RE: Simplex Algorithm - Albert Chan - 11-20-2023, 06:12 PM
RE: Simplex Algorithm - ftneek - 11-21-2023, 08:36 AM
RE: Simplex Algorithm - Albert Chan - 11-21-2023, 02:05 PM
RE: Simplex Algorithm - ftneek - 11-19-2023, 08:02 PM
RE: Simplex Algorithm - ftneek - 11-20-2023, 12:18 AM
RE: Simplex Algorithm - Albert Chan - 11-20-2023, 02:14 AM
RE: Simplex Algorithm - ftneek - 11-20-2023, 09:02 AM
RE: Simplex Algorithm - Albert Chan - 11-20-2023, 11:42 AM
RE: Simplex Algorithm - Albert Chan - 11-20-2023, 03:34 PM
RE: Simplex Algorithm - ftneek - 11-20-2023, 07:52 PM
RE: Simplex Algorithm - Albert Chan - 11-21-2023, 05:58 PM
RE: Simplex Algorithm - Albert Chan - 11-21-2023, 11:20 PM
RE: Simplex Algorithm - Albert Chan - 11-22-2023, 06:44 PM
RE: Simplex Algorithm - Albert Chan - 11-22-2023, 10:10 PM
RE: Simplex Algorithm - Albert Chan - 12-24-2023, 03:46 PM
RE: Simplex Algorithm - ftneek - 12-24-2023, 07:32 PM
RE: Simplex Algorithm - Albert Chan - 12-24-2023, 08:05 PM
RE: Simplex Algorithm - ftneek - 11-23-2023, 01:23 AM
RE: Simplex Algorithm - Albert Chan - 11-23-2023, 06:35 AM
RE: Simplex Algorithm - ftneek - 12-22-2023, 07:38 AM
RE: Simplex Algorithm - Albert Chan - 12-22-2023, 04:07 PM
RE: Simplex Algorithm - ftneek - 12-22-2023, 07:28 PM
RE: Simplex Algorithm - Albert Chan - 12-23-2023, 04:44 AM
RE: Simplex Algorithm - ftneek - 12-23-2023, 07:46 AM
RE: Simplex Algorithm - Albert Chan - 12-23-2023, 10:23 AM
RE: Simplex Algorithm - ftneek - 12-23-2023, 09:30 PM
RE: Simplex Algorithm - ftneek - 01-07-2024, 02:40 AM



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