How to create array with unequal spacing?

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Ahmad Hasnain 2018-2-21

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https://ww2.mathworks.cn/matlabcentral/answers/383997-how-to-create-array-with-unequal-spacing

评论： Walter Roberson 2018-2-22

采纳的回答： Walter Roberson

I want to create an array with unequal spacing. I have h = 1 1/2 1/4 1/8 ..... 2^-60.

Every second entry in this array is 1/2 of the last one. I only know, how to make arrays with equal spacing.

a = 1:5:40

But how do I create array that gets halved with every entry?

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Stephen23 2018-2-22

@Walter Roberson: Interesting. So what is the usecase for pow2(n) then?

Walter Roberson 2018-2-22

In 2.^-(0:60) the JIT is detecting that the expression is constant and optimizes it, at least in the case of re-use. If you use B = 2; B.^-(0:60) or if you use V = -(0:60); 2.^B then JIT optimization is not as good and pow2 can have better performance than those.

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