# Elegant fractions in one line for partial derivatives

1. I've learned from the TeXbook and from https://tex.stackexchange.com/a/128498/1340 that textmode fractions are often best written in slashed form. Looking at my manuscript I just ran into $\frac{\partial t}{\partial x}$, but partial derivatives in slashed form seem to be much less common (though I've indeed seen them sometimes, but others dislike them too, e.g., see comment How do I write the partial derivatives without partitioning?), especially when parentheses are needed.

What's typographically appropriate there?

2. In fact, my actual code is $\frac{\partial t}{\partial x, d_x}$, because this isn't really calculus but some other notation (it's only inspired from partial derivatives) from a PhD thesis—which seems to never use slashed form. Still, if slashed form $(\partial t)/(\partial x, d_x)$ is appropriate I could use it.

EDIT: I know the , d_x seems to make no sense—again, these are not actual partial derivatives. (I can link to the actual source but that's really off-topic).

• choice of notation is normally considered off topic here, put personally I wouldn't use the / form for partial derivatives either \frac form or if inline use is more common switch to a D_{xyz} style of notation. Jul 20, 2017 at 19:43 \documentclass{article}
\usepackage{xfrac}
\usepackage{mathtools}

\begin{document}

$\frac{\partial t}{\partial x, d_x} \qquad \sfrac{\partial t}{\partial x, d_x} \qquad \sfrac{\partial t}{\partial x}\cdot\sfrac{1}{d_x}$

\end{document}


• The question is probably off topic.
• Anyway -- I like the slashed version better :).
• I do not understand the ,d_x part -- are you sure that is correct?
• Better use \sfrac from the xfrac package. It remedies many of nicefrac's shortcomings and \sfrac is less typing than \nicefrac. Jul 20, 2017 at 23:31
• Good idea. Feel free to edit the answer. Jul 20, 2017 at 23:41
• the (middle) slashed form doesn't look like it has the same meaning as the \frac form. adding parentheses around the denominator would make them obviously equivalent. Jul 21, 2017 at 1:47
• @barbarabeeton Yes, also my opinion. I just was out of time/motivation yesterday night. Jul 21, 2017 at 9:55

You could use the index notation. This is somewhat common in physics.

\documentclass{article}
\begin{document}

$\frac{\partial t}{\partial x, d_x} \equiv \partial_{x, d_x} t$

\end{document} • To be sure: that's probably $\partial_x t$ (or $\partial_{x, d_x} t$) based on https://en.wikipedia.org/wiki/Partial_derivative#Notation and on the fact that x is the independent variables that t depends on (and d_x`... sorry, don't ask). If so, I get it, and it seems a pretty clever idea. Jul 20, 2017 at 23:43
• @Blaisorblade Of course, you're right. I messed up the order. I fixed my answer. Jul 20, 2017 at 23:45
• Oh thanks—I was really wondering for a long moment! Jul 21, 2017 at 0:08