associated-sorting

Sorting eigenvectors by their eigenvalues (associated sorting)

I have an unsorted vector of eigenvalues and a related matrix of eigenvectors. I'd like to sort the columns of the matrix with respect to the sorted set of eigenvalues. (e.g., if eigenvalue[3] moves to eigenvalue[2], I want column 3 of the eigenvector matrix to move over to column 2.) I know I can sort the eigenvalues in O(N log N) via ...

Sorting results by 'most relevent' - MYSQL & PHP

I've never really considered this question before and wondered if anyone has any advice or input on best practices for achieving 'relevent results'. In my case I'm running a search query that includes full text searching across 5 fields, a geographic radial lookup and a number of basic comparisons. I can prioritise the fields I'm most ...