# Distinguishing between comma in list of numbers and in text

I am writing the following mathematical definition:

... where for $i=1,\dotsc,n$, $Ag_i=(AS_i,\mathscr{K}_i)$, ...


which produces: There are two kind of commas, one in 1, …, n and the other after n which is in text. How is it possible to make the two kinds of commas distinguishable so then it does not appear as though there is a missing formula after n.

• The best way is to add some text between the list of numbers and $Ag_i=...$, or inverting: where $Ag_i=...$, for $i=1,\dots,n$. Note that you don't need \dotsc, only \dots suffices because it's smart enough to see a comma follows and adjust itself. – egreg Sep 24 '13 at 10:06
• @egreg Thanks. Because of the structure of the sentence I cannot change the order of the two elements (since there are more conditions after Agi=(ASi,Ki)). Thanks for the tip on dotsc. I'll change it. – Ali Sep 24 '13 at 10:32
• You could use ; instead of , after n. – Mensch Sep 24 '13 at 11:23
• If I don't find any way of making the two types of commas more distinguishable and different, then I think using ; would be the best solution. Thanks. – Ali Sep 24 '13 at 13:28
• – Qrrbrbirlbel Sep 24 '13 at 14:22

There are not many possibilities to distinguish these commas. As you can see, the math-mode and text-mode comma looks the same. You could redefine the font for the math-mode comma or set the single appearing text-mode comma locally in an other font, but that will look weird, I guess.

I am collecting the comments together with my own thoughts for other possibilities:

• invert the sentence to get text between the two mathematical expressions
• use some other text separator such as the semicolon
• use some other math separator such as slash or semicolon
• separate the first mathematical expression by brackets where (for $i=1,\dots,n$) $Ag_i=(AS_i,\mathscr{K}_i)$, or other stuff is ...
• add some space with \quad or \qquad behind the first mathematical expressions to get a bigger visual separation

All this points are not really beautiful and as you tagged with "typography", you should consider to do, what I would do.

Rewrite the whole sentence. It is not forbidden to split in several sentences and to guide the reader through your text. This could look like:

In the following, I will present some formulae, including the counter $i$ which is defined as $i=1,\dotsc,n$. The possible formulae are $Ag_i=(AS_i,\mathscr{K}_i)$, ...