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 $|x|$ means, it means the absolute value of x, which is the distance from 0. $|x|=\sqrt{x^2}$

and if you are asking what $||x||$ 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 $|x|$ means, it means the absolute value of x, which is the distance from 0. $|x|=\sqrt{x^2}$

and if you are asking what $||x||$ 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||.