Make the vector lin=[1 2 3 ⋯ 20] (the integers from 1 to 20), and then make every other value in it negative to get lin=[1 −2 3 −4 ⋯ −20] . what is the MATLAB code?

lin=[1:20]

then?

Answer 1

[Matt J]

   lin(2:2:end)=-lin(2:2:end)

[Orbay Altuntoprak]

Having looked through google for the answer to the question stated above, I was very delighted to find your answer. Thank you.

Answer 2

[Azzi Abdelmalek]

a=-(1:20)

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