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== gprof ==
Each sample counts as 0.01 seconds.
% cumulative self self total
time seconds seconds calls s/call s/call name
89.19 97.08 97.08 main
4.73 102.22 5.14 1406087506 0.00 0.00 std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >::operator[](unsigned int)
4.49 107.11 4.88 1406087506 0.00 0.00 std::vector<double, std::allocator<double> >::operator[](unsigned int)
== Potential Speed Increase ==
Using Amdahls Law ---- > Sn = 1 / ( 1 - P + P/n )
We can examine how fast out program is capable of increasing its speed
P = 80%; n = 480
S480 = 1 / ( 1 - 0.80 + 0.80 / 480 ) = 4.96
At best, we expect the process time to drop from 0.21 secs to about 0.21 / 4.96 = 0.04 secs.
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Gustafsons Law S(n) = n - ( 1 - P ) ∙ ( n - 1 )
P = 50% n = 10
S = 10 - ( 1 - .50 ) * ( 10 - 1 ) = 5.5