title: what is 1-norm mean?
body: <p>When I reading paper, I found 1-norm or 2-norm. like this: <a href="https://i.stack.imgur.com/ifETP.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ifETP.png" alt="enter image description here"></a>
  However, I can not understand this word? Is it mean that the normal distribution with mean 1?</p>