replacing values in a vector with new value?

Basically, I have a large vector and want to add 180 to all the negative values and subtract 180 to all positive values in the vector. Finally, I should have the same size vector with the changes. Appreciate a helping hand

[Azzi Abdelmalek]

This is almost the same question you posted here http://www.mathworks.com/matlabcentral/answers/300057-i-want-add-a-value-to-every-element-that-is-less-than-zero-in-my-vector#comment_386034

Answer 1

[James Tursa]

v = your vector
n = v < 0; % the negative indexes (logical)
p = v > 0; % the positive indexes (logical)
v(n) = v(n) + 180;
v(p) = v(p) - 180;

Note: This doesn't change any exact 0 values, per your description.

Answer 2

[Image Analyst]

Try this:

v = v - sign(v) * 180

where v is your vector. It will do what you asked for.