Question: Consider the Gaxpy Update y = y + Ac with A R***, ~ ER and y ER. (a) Derive two algorithms for its computation. The

Consider the Gaxpy Update y = y + Ac with A

Consider the Gaxpy Update y = y + Ac with A R***, ~ ER" and y ER". (a) Derive two algorithms for its computation. The first should access A by row and the second by column. Present them mathematically and implement them in matlab (or any other language you wish, but you should identify it). (b) Time the execution of the two implementations for n = 1000 (feel free to use other values, eg. n = 10,000) using matlab's tic, toc and explain why the two algorithms differ by almost an order of magnitude. Run your code at least five times in order to get some statistical significance. Consider the Gaxpy Update y = y + Ac with A R***, ~ ER" and y ER". (a) Derive two algorithms for its computation. The first should access A by row and the second by column. Present them mathematically and implement them in matlab (or any other language you wish, but you should identify it). (b) Time the execution of the two implementations for n = 1000 (feel free to use other values, eg. n = 10,000) using matlab's tic, toc and explain why the two algorithms differ by almost an order of magnitude. Run your code at least five times in order to get some statistical significance

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