document: Limits for computational electromagnetics codes imposed by computer architecture The algorithmic complexity of the innermost loops that determine the complexity of algorithms in computational electromagnetics -LRB- CEM -RRB- codes are analyzed according to their operation count and the impact of the underlying computer hardware . As memory chips are much slower than arithmetic processors , codes that involve a high data movement compared to the number of arithmetic operations are executed comparatively slower . Hence , matrix-matrix multiplications are much faster than matrix-vector multiplications . It is seen that it is not sufficient to compare only the complexity , but also the actual performance of algorithms to judge on faster execution . Implications involve FDTD loops , LU factorizations , and iterative solvers for dense matrices . Run times on two reference platforms , namely an Athlon 900 MHz and an HP PA 8600 processor , verify the findings
doc_bio_tags: O O B I I O O B I O B I O O B I O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O B I O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O