Global Astrometric Solutions with Sparse Matrix Techniques
نویسندگان
چکیده
منابع مشابه
Global Astrometric Solutions with Sparse Matrix Techniques
Modern astrometric techniques lead to large, linear systems solved by the precepts of least-squares. These systems are usually sparse, and one should take advantage of the sparsity to facilitate their solution. As long as the matrix A of the equations of condition possesses the weak Hall property, characteristic of linear systems derived from astrometric reductions, it is possible to nd a spars...
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information to fetch data and to perform the computation. Such runtime preprocessing techniques have been fairly well-studied and successfully incorporated into compilers [14, 6]. The inspector/executor method incurs a runtime overhead for each inspector stage which are greatly increased when references use multiple levels of indirection. To reduce these overheads in sparse-matrix problems, the...
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Sparse matrix problems are diicult to parallelize eeciently on distributed memory machines since data is often accessed indirectly. Inspector/executor strategies, which are typically used to parallelize loops with indirect references, incur substantial run-time preprocessing overheads when references with multiple levels of indirection are encountered | a frequent occurrence in sparse matrix al...
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ژورنال
عنوان ژورنال: International Astronomical Union Colloquium
سال: 2000
ISSN: 0252-9211
DOI: 10.1017/s0252921100000221