# Symbol for “such that” (not in set) [duplicate]

If a is a set

a \leftarrow { b| b must satisfies property}


but if a is an element

a \leftarrow b| b must satisfies property


is this a usual notation? Or what other symbol should I use for the "such that" (|) symbol?

-

## marked as duplicate by Werner, yo', Claudio Fiandrino, lockstep, KurtFeb 20 '13 at 17:56

This question was marked as an exact duplicate of an existing question.

You can use \mid. – egreg Feb 20 '13 at 10:31
I have never seen such a notation, and it is confusing, too: what happens when there are several b that satisfy the condition? Which one gets assigned to a? – mafp Feb 20 '13 at 10:34
As egreg points out, \mid seems to be a good choice. Otherwise, you can try and find the symbol using either Detexify (detexify.kirelabs.org/classify.html) or the Comprehensive LaTeX Symbol List (mirrors.dotsrc.org/ctan/info/symbols/comprehensive/…). – Svend Tveskæg Feb 20 '13 at 10:48
If you really ask about a mathematical notation and not about a way how to typeset it in (La)TeX, you should better ask on math.SE ;) – yo' Feb 20 '13 at 17:02
@william007 You first have to define how you make the assignment well defined, i.e., how do you ensure that exactly one b is selected. If, e.g., you chose a minimal b, then a \leftarrow \argmin \{b \mid b\text{ fulfils } P\} would do. – mafp Feb 20 '13 at 21:23