Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>This problem is called the stable marriage problem </p> <p>The idea of the algorithm to solve such a problem is that each of your segments will successively be assigned to the next label on its preference list that is not already assigned to a segment it prefers.</p> <p>This will converge towards an optimal matching (note that there can be more than one).</p> <p>Here is a java example (I didn't test it that much, use at your own risk ;) )</p> <pre><code>class SMP { static int[] segments = {16, 19, 22, 26}; static String[] labels = {"horse", "cow", "mule"}; static int[][] labelIndicesForSegments = {{0, 1, 2}, {0, 2}, {2, 1, 0}, {2}}; static int[][] segmentIndicesForLabels = {{3, 1, 2, 0}, {0, 2, 1}, {3, 2, 1}}; static int[] matching = new int[segments.length]; static int[] nextLabel = new int[segments.length]; // A simple pointer to the next label to test for each segment (the current position in its own preference list) public static void main(String[] args) { // initialize all matchings for (int i=0; i&lt;matching.length; i++) { matching[i] = -1; nextLabel[i] = 0; } // While there is at least one free label and one free segment while (canEnhance()) { int unmatched = findUnmatchedSegment(); // Pick an unmatched segment int label = labelIndicesForSegments[unmatched][nextLabel[unmatched]]; nextLabel[unmatched]++; int matchedSegment = getMatchedSegment(label); if (matchedSegment == -1) { // The label is not matched matching[unmatched] = label; } else { if (labelPrefersSegment(label, matchedSegment, unmatched)) { matching[unmatched] = label; matching[matchedSegment] = -1; } } for (int i = 0; i &lt; matching.length; i++) { if (matching[i] != -1) System.out.println("Segment "+segments[i]+" matched with label "+labels[matching[i]]); } System.out.println("-----"); } for (int i = 0; i &lt; matching.length; i++) { if (matching[i] != -1) System.out.println("Segment "+segments[i]+" matched with label "+labels[matching[i]]); } } public static boolean labelPrefersSegment(int label, int currentSegment, int newSegment) { int[] preferenceList = segmentIndicesForLabels[label]; for (int i = 0; i &lt; preferenceList.length; i++) { if (preferenceList[i] == currentSegment) return false; if (preferenceList[i] == newSegment) return true; } return false; } public static int getMatchedSegment(int label) { for (int i=0; i&lt;matching.length; i++) { if (matching[i] == label) return i; } return -1; } public static int findUnmatchedSegment() { for (int i=0; i&lt;matching.length; i++) { // The segment need to be free and to still have labels to test if (matching[i] == -1 &amp;&amp; nextLabel[i] &lt; labelIndicesForSegments[i].length) { return i; } } return -1; } public static boolean canEnhance() { return findUnmatchedSegment() != -1; } } </code></pre> <p>You could do better using a more object-oriented approach but that's a start :)</p> <p>The essential part is in the while loop, the small functions after the main are not that interesting :)</p> <p>You can find more infos there : <a href="https://en.wikipedia.org/wiki/Stable_marriage_problem" rel="nofollow">https://en.wikipedia.org/wiki/Stable_marriage_problem</a></p> <p>Cheers</p>
    singulars
    1. This table or related slice is empty.
    1. POCombine two lists of indices to create a 1-1 mapping between two other lists
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USTamere
    1. USTamere
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POCombine two lists of indices to create a 1-1 mapping between two other lists
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTDownMod
    1. This table or related slice is empty.
 

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