# Thread: what is this symbol

1. ## what is this symbol

$\displaystyle \prec$
$\displaystyle \preceq$
$\displaystyle \succ$
$\displaystyle \succeq$?
I don't know what to search for to learn about it. Typing Succ or Prec just returns latex symbol tables. I'm using them in mathematical programming, but in practice just replacing them by the corresponding $\displaystyle \le, \ge$, etc. What do they mean more generally?

2. Originally Posted by coolnessitself
$\displaystyle \prec$
$\displaystyle \preceq$
$\displaystyle \succ$
$\displaystyle \succeq$?
I don't know what to search for to learn about it. Typing Succ or Prec just returns latex symbol tables. I'm using them in mathematical programming, but in practice just replacing them by the corresponding $\displaystyle \le, \ge$, etc. What do they mean more generally?
They could mean a lot of things in a lot of different contexts. They could mean subgroup in group theory, dominated by in the context of limits, etc.

3. is there a name for them that I can search by? Succ doesn't turn up any math-related results, only latex results.

My specific application is relaxing a constraint X-Y=0 to a semi-definite constraint X-Y \succeq 0.

4. Originally Posted by coolnessitself
$\displaystyle \prec$
$\displaystyle \preceq$
$\displaystyle \succ$
$\displaystyle \succeq$?
I don't know what to search for to learn about it. Typing Succ or Prec just returns latex symbol tables. I'm using them in mathematical programming, but in practice just replacing them by the corresponding $\displaystyle \le, \ge$, etc. What do they mean more generally?
They may have several different meaning.
However, they are most often used is discussing a partially ordered set.
$\displaystyle a\preceq b$ “a proceeds b”. (a could be b)
$\displaystyle c\succ d$ “c strictly succeeds d”. (c and d are distinct).