1. ## opeartor ||X||

whats the || operator used as: ||X||
or what is this ( || ) notation called

2. It's the symbol for a vector norm.

Norm (mathematics) - Wikipedia, the free encyclopedia

3. Originally Posted by amrita.jain
whats the || operator used as: ||X||
or what is this ( || ) notation called
If you are asking what $\displaystyle |x|$ means, it means the absolute value of x, which is the distance from 0. $\displaystyle |x|=\sqrt{x^2}$

and if you are asking what $\displaystyle ||x||$ means, I have only seen that as the magnitude of a vector

4. Hello,

I stopped my reading at the first line of mathstud

tired... *scuzi*

5. Originally Posted by amrita.jain
whats the || operator used as: ||X||
or what is this ( || ) notation called
Originally Posted by Mathstud28
If you are asking what $\displaystyle |x|$ means, it means the absolute value of x, which is the distance from 0. $\displaystyle |x|=\sqrt{x^2}$

and if you are asking what $\displaystyle ||x||$ means, I have only seen that as the magnitude of a vector
Originally Posted by Moo
Hello,

The absolute value is just a particular norm, dimension 1. The question has been clearly asked, with ||X||.

While I am not one to stand up for Mathstud, the notation the OP used in the brackets is that for absolute value. He(Mathstud) also did give the answer to both possibilities.

6. While I am not one to stand up for Mathstud

7. thanks all for the reply
and spl thanks to sean.1986..i get it now