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This is my first time here and I did my best to figure out if such a question is in place here. If I missed something I apologize.

My questions is how can I mark a power set in the lyx document editor?

For example: I'd like to write P(A) when A represents a set, but in the special marking normally used for the power set. I assume there should be a '\shortcut' kind of thing, but I'm new to lyx and can't find one.

Thanks in advance...

Math PhD Student
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Yekhezkel Yovel
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  • Welcome to TeX.SX! You have been migrated here. Please register to this site with the same account as on mathoverflow.net! Could you please explain a bit, how you would like the P(A) to look like? If necessary, draw a picture. I can't help you on LyX, but many people will be able to write some LaTeX \shortcut (called macro) for you. – LaRiFaRi Nov 24 '14 at 13:49
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    There are several common ways to denote power set, for example $\mathcal{P}(A)$, even plain $P(A)$ is fine. Just please do not abuse for this purpose the Weierstraß elliptic function symbol $\wp$, as many clueless people do. – Emil Jeřábek Nov 24 '14 at 15:20
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    Thank you both very much. @EmilJeřábek, $\mathcal{P}(A)$ was exactly what I was looking for - Would make a valid answer... That's how it looks in my homework pages. @LaRiFaRi, thanks for naming the macro for me, this will help me a lot in future questions. I was afraid this group didn't like ignorant LYX users as myself, Thanks for the nice welcome... – Yekhezkel Yovel Nov 25 '14 at 09:49
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    @EmilJeřábek consider transforming your comment into an answer. It will make it more noticeable for others (and you will get the reputation you deserve). – Stefan van den Akker Apr 02 '17 at 09:19

3 Answers3

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I find that $\mathcal{P} (\mathbb{A})$ gives me the result I want:

rendered

jarhill0
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$\frak{P} (\mathbb{A})$ also works.

Werner
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user90781
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Let's assume you want the output of your power set to resemble something like this:

enter image description here

The above requires amssymb to show the special P. For this, "load always" Document > Settings > Math Options > amssymb:

enter image description here

Now, there are a couple of ways to do this:

  1. Pure LyX

    At the start of your document, Insert > Math > Macro... For the newcommandname, type powerset. For the TeX component of the math macro, type \mathbb P, →, (\#1). Leave the LyX component of the math macro empty.

    Now when you type a regular (inline) math formula (Insert > Math > Inline Formula), typing \powerset changes the input to use your macro:

    enter image description here

  2. Pure LaTeX

    In your Document > Settings... > LaTeX Preamble, add

    \newcommand{\powerset}[1]{\mathbb{P}(#1)}

    Within any (inline) math formula, insert an ERT

    enter image description here

For more information, see How to enter Math Macros.

Werner
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