Subtracting the next element on a vector? Basic

If I have a vector with n elements, and want a new vector with the subtraction of the first by the second element, and continues...

For exemple: A = [20, 8, 4, 1] turns into B = [(20-8),(8-4),(4,1)]

I started something with

n = length(A);

for k = 1:n

....

but nothing I tried worked them.

Thanks.

Answer 1

[Jiro Doke]

A = [20, 8, 4, 1];
B = -diff(A);

[Renato de Sá]

Thank you, sir.

[Steven Lord]

Jayaram ram flagged this as "its working good sir...."

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