-Work Parallel Algorithm for Finding the Row Minima in Totally Monotone Matrices∗
نویسندگان
چکیده
We give a parallel algorithm for computing all row minima in a totally monotone n×nmatrix which is simpler and more work efficient than previous polylogtime algorithms. It runs in O(lg n lg lg n) time doing O(n √ lg n) work on a CRCW PRAM, in O(lg n(lg lg n)2) time doing O(n √ lg n) work on a CREW PRAM, and in O(lg n √ lg n lg lg n) time doing O(n √ lg n lg lg n) work on an EREW PRAM.
منابع مشابه
Efficient Matrix Chain Ordering in Polylog Time
The matrix chain ordering problem is to find the cheapest way to multiply a chain of n matrices, where the matrices are pairwise compatible but of varying dimensions. Here we give several new parallel algorithms including O(lg3 n)-time and n/lgn-processor algorithms for solving the matrix chain ordering problem and for solving an optimal triangulation problem of convex polygons on the common CR...
متن کاملMore Efficient Parallel Totally Monotone Matrix Searching
We give a parallel algorithm for computing all row minima in a totally monotone n = n matrix which is simpler and more work efficient than previous polylog-time Ž . Ž . algorithms. It runs in O lg n lg lg n time doing O n lg n work on a CRCW ' 2 Ž Ž . . Ž . PRAM, in O lg n lg lg n time doing O n lg n work on a CREW PRAM, and in ' Ž . Ž . O lg n lg n lg lg n time doing O n lg n lg lg n work on a...
متن کاملSorting and Selecting in Totally Monotone
An mn matrix A is called totally monotone if for all i1 < i2 and j1 < j2, Ai1; j1] > Ai1; j2] implies Ai2; j1] > Ai2; j2]. We consider the complexity of comparison-based selection and sorting algorithms in such matrices. Although our selection algorithm counts only comparisons its advantage on all previous work is that it can also handle selection of elements of diierent (and arbitrary) ranks i...
متن کاملAn Efficient Algorithm for Row Minima Computations on Basic Reconfigurable Meshes
A matrix A of size m n containing items from a totally ordered universe is termed monotone if, for every i, j, 1 i < j m, the minimum value in row j lies below or to the right of the minimum in row i. Monotone matrices, and variations thereof, are known to have many important applications. In particular, the problem of computing the row minima of a monotone matrix is of import in image pr...
متن کاملLinkk Oping Electronic Articles in This Work Has Beensubmitted for Publication Elsewhere. Parallel Algorithms for Searching Monotone Matrices on Coarse Grained Multicomputers Linkk Oping Electronic Articles in Computer and Information Science
We present parallel algorithms for geometric problems on coarse grained multicomputers More speci cally for a square mesh connected p processor computer we show that The implicit row maxima problem on a totally monotone n nmatrix can be solved in O n p log p time if n p The all farthest neighbors problem for a convex n gon can be solved in O n p p time if n p The maximum perimeter triangle insc...
متن کامل