I am initializing vector by randn function (two ways).
1.
clc
clear all
N = 1e6;
x = zeros(N, 1);
tic
for k = 1 : N
x(k) = randn;
end
toc
Elapsed time is 0.054535 seconds.
2.
clc
clear all
N = 1e6;
x = zeros(N, 1);
tic
for k = 1 : N
x(k) = randn(1,1);
end
toc
Elapsed time is 1.491623 seconds.
In both cases function randn returns one element (array 1x1), but elapsed time differs by ~30 times. Why?
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