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My teacher is teaching us about sets, and he said that the '|', the ':' and the '\' symbols can be used to mean 'such that'. I'm certain of the first two, but I searched a little and couldn't find reference to the last. Does it exist for this purpose? If it's a special character, what Unicode code point does it have?

Thanks in advance.

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    I use a semicolon, like so: $\{x ∈ X;\; φ(x)\}$. A professor of mine did so and I adapted this as well because it looks good and the semicolon is almost never used in any other way (as opposed to “$|$” or “$:$”).2014-02-13

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We usually use ":" and "|", as in $\{ x \in \mathbb{R} : x > 0\}$. Hope that answers your question.

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I had a professor use a backwards "element of ($\in$) " sign to stand for "such that". He's the only one I've seen do it, and it very well could be unique to him. But there are probably many people with their own unique, preferred symbols. I wasn't a fan of it, so I stick to the basic ":" and "|", depending on how many other vertical lines are in the set description.

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    For abbreviating *such that*, I have a professor who likes to use the dollar sign $\$$. He says it looks like the letters s and t superimposed. I actually got used to it really quickly.2014-01-31