Question

Suppose a numerical algorithm requires the solution of a 71x71 linear system of equations 326 times, where the only thing changing each time is the right hand side vector. Effective use of LU factorization can reduce the computational cost of this step by approximately percent compared to using MATLAB left division alone. (Enter your answer in percent to two decimal places.)

Answer 1

Total number of calculation=71*326=23146

when only normal method is used for findinf values total no of calculations=(71*70*326)/2

=810110

Therefore No of calculations reduced = ((810110-23146)/810110)*100 %

=97.14%