Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <pre><code>REQUIREMENTS for the BALANCED ROUND ROBIN algorithm The requirements of the algorithm can be defined by these four rules: 1) All versus all Each team must meet exactly once, and once only, the other teams in the division league. If the division is composed of n teams, the championship takes place in the n-1 rounds. 2) Alternations HOME / AWAY rule The sequence of alternations HOME / AWAY matches for every teams in the division league, should be retained if possible. For any team in the division league at most once in the sequence of consecutive matches HAHA, occurs the BREAK of the rhythm, i.e. HH or AA match in the two consecutive rounds. 3) The rule of the last slot number The team with the highest slot number must always be positioned in the last row of the grid. For each subsequent iteration the highest slot number of grid alternates left and right position; left column (home) and right (away). The system used to compose the league schedule is "counter-clockwise circuit." In the construction of matches in one round of the championship, a division with an even number of teams. If in a division is present odd number of teams, it will be inserted a BYE/Dummy team in the highest slot number of grid/ring. 4) HH and AA are non-terminal and not initial Cadence HH or AA must never happen at the beginning or at the end of the of matches for any team in the division. Corrective inversion RULE performs only once, in the bottom line in the RING, LeftRight redundant inversion flip-flop RULE, so we will never obtain in the last two rounds CC or FF. Round Robin ALGORITHM The algorithm that satisfies rule (1) is obtained with a simple algorithm Round Robin: where every successive round is obtained applying to the slot numbers ring a "counterclockwise" rotation. To satisfy the rule (2) we must "improve", the simple round robin algorithm by performing balancing of Home and Away sequence. It is performed by applying several "counterclockwise" rotations in the slot numbers ring in order to obtain acceptable combinations of slot positions for the next round. The number of rotations required in the ring is (n / 2 -1). So we will get that in the two successive rounds, almost all the teams playing at home in the previous round, will play away from home in the next round. DATA STRUCTURE n_teams: (4,6,8,..,20) n_rounds: n_teams -1; </code></pre> <p>Ring – Circuit Ring is such data structure, i.e. a particular type of sequence where are performable and formally algorithmically defined: operation of (anti-clockwise) ROTATION among ring elements and the operation INSERT_LAST_TEAM, The ring content defines all matches for the each particular round in match schedule Ring.Length is an even number equal to n_teams Left_ring sub-sequence: The Ring sub-sequence with elements from 1 to n/2. Right_ring sub-sequence: Ring sub-sequence with elements from n/2+1 to n. Match [i] = Ring_element [ i ] : Ring_element [ n – i + 1 ]; where i = 1 to n/2 The MATCH is an ordered pair composed of two TEAMS, (Home_team : Away_team). 1st Round Home : Away 01:07 02:06 03:05 04:08</p> <pre><code>Next_Iteration is obtained by applying these rules: a) perform (n/2 – 1) times * ANTI CLOCKWISE ROTATIONs b) all right column elements, below the last team, will be shifted upwards c) INSERT_LAST_TEAM (Insert_Last_Element_into_ Ring_onLeft (n) or Insert_Last_Element_into_Ring_onRight(n), alternatively) d.1) Last Line LeftRight redundant swap RULE eventually have to swap elements in the last row once again d.1) last team left/right - flip/flop In the following example it will be explained how the Ring elements of 8 teams are gradually transformed in five steps, from from the SECOND ROUND into the THIRD ROUND. If we start from from the SECOND ROUND: 05 :04 06 :03 07 :02 08 :01 a. After we perform THREE Anti-clockwise rotations, (n =8, 3 = 8/2 -1) we will get the situation like this: 02 :01 03 :08 04 :07 05 :06 b. When we apply the LAST SLOT RULE: the right column elements (06,07) below last team (08) will be shifted upwards 02 :01 03 04 :07 05 :06 c. And now we will apply the LAST SLOT RULE-bottom right, we will get the situation which describes the THIRD ROUND: (08 must be moved to the bottom right position) 02 :01 03 :07 04 :06 05 :08 d.1 Now it will be checked if for this iteration number (i.e. round) depending on CODE SIX or ZERO Cadence, we eventually have to swap elements in the last row redundantly, Left/Right swaping d.2 And at the end we will apply the LAST TEAM SLOT ROULE swap left &amp; right elements, if in the previous iteration last team was positioned on the right, in this iteration it should be positioned on the left bottom position, so the last line elements will be swapped, else do nothing. THIRD ROUND: 02 :01 03 :07 04 :06 05 :08 </code></pre> <p><a href="http://www.constellationsystems.net/constellation/constellation_algorithm_balanced_round_robin_bis/" rel="nofollow">read more</a></p> <p><a href="http://www.constellationsystems.net/constellation/perl_code_balanced_round_robin_bis/" rel="nofollow">Here is the snippet of the code in Perl.</a></p>
    singulars
    1. This table or related slice is empty.
    1. POGenerating natural schedule for a sports league
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USjjpcondor
    1. USjjpcondor
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTDownMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTModeratorReview
    1. COIt's quite difficult to understand your answer — please copy-and-paste more selectively to explain how the page you linked to is relevant to the original question, and perhaps provide a code (or pseudo-code) overview of how Björn might make use of these algorithms.
      singulars
      1. PO
      1. USsupervacuo
    2. COHere is the snippet of the code in Perl .. http://www.constellationsystems.net/constellation/perl_code_balanced_round_robin_bis/
      singulars
      1. PO
      1. USjjpcondor
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload