# Numbers are very small in numerator and denominator using \frac

When I use the \frac command, I notice that the characters used for the fraction terms become smaller than those which are not in the \frac command. Is there a way to correct it?

• Well, this is normal, isn't it? That is 1.5 shouldn't appear as 11/2 and the standard formatting uses a smaller 1 and 2 for the 1/2 precisely to show that they are the numerator and denominator. – cfr Mar 28 '15 at 18:21
• There is a reason: a big fraction in text will spread lines apart and that's bad. Prefer the slashed form for inline fractions: $1/2$ instead of $\frac{1}{2}$. – egreg Mar 28 '15 at 18:24

A larger (nicer?) version of the fraction can be obtained with \dfrac.

\documentclass{article}

\usepackage{mathtools}
\begin{document}

\begin{align}
\gamma &= \frac{1}{\sqrt{1-\frac{v^2}{c^2}}} \\
& \notag \\
\gamma &= \dfrac{1}{\sqrt{1-\dfrac{v^2}{c^2}}}
\end{align}

\end{document}


• but please don't use this form in text, only in display. – barbara beeton Mar 28 '15 at 19:32
• thank you very much Barbara , and why is that ? – Farzad64 Mar 29 '15 at 0:41
• @barbarabeeton: The OP did not mention text mode ... – user31729 Mar 29 '15 at 7:10
• true, but the op didn't specify display mode either. it makes a difference. actually, while i agree totally with using \dfrac for the "outer" one in your example, i think using it within the root is too much. the "intermediate" size (mentioned in another comment) is a good option here. – barbara beeton Mar 29 '15 at 13:35
• @barbarabeeton: that's true too, but I had no impression that inline fractions are used. I used an align environment for true math, not inline, otherwise nicefrac or xfrac are the right choice – user31729 Mar 29 '15 at 18:17

For fractions, nicefrac may be preferred. Here's a comparison:

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage{textcomp}
\usepackage{nicefrac}

\begin{document}
This is some text with a $\frac{1}{2}$ in it.

This is some text with a \textonehalf{} in it.

This is some text with a \nicefrac{1}{2} in it.
\end{document}


Another solution would be to use medium-sized fractions (~ 80% of displaystyle, defined in nccmath), plus a slight increase of \baselineskip with setstretch. Forlarge operators, theis a \medop command:

\documentclass{article}

\documentclass{article}

\usepackage[T1]{fontenc}
\usepackage{textcomp}
\usepackage{nccmath}
\usepackage{setspace}
\setstretch{1.1}

\begin{document}

This is some text without fractions.

This is some text without fractions. This is some text without fractions.

This is some text with a $\mfrac{1}{2}$ in it: $p(x,y) = \medop\sum_{m=1}^{\infty} \medop\sum_{n=1}^{\infty} p_{mn} \sin \bigl(\mfrac{m \pi x}{a}\bigr) \sin \bigl(\mfrac{n \pi y}{b}\bigr)$

This is again some text without fractions. Again some text without fractions.

\end{document}


• There is one problem , if i use dfrac in this formula , some characters are small , some are big : $p(x,y) = \sum_{m=1}^{\infty} \sum_{n=1}^{\infty} p_{mn} sin (\dfrac{m \pi x}{a}) sin (\dfrac{n \pi y}{b})$ – Farzad64 Mar 29 '15 at 11:34
• You shouldn't use \dfrac for in-line formulae, unless you accept the interline skips be unequal! Note it is possible to obtain medium-sized operators like \sum, \prod, &c. See my updated answer. Btw, if you want to type the sine function, and not the product of 3 variables s, i, n, you should type \sin with a backslash. – Bernard Mar 29 '15 at 12:02
• You're welcome. Glad to be useful. – Bernard Mar 29 '15 at 12:56

You can use \dfrac for larger fractions with bigger numbers. \dfrac belongs to the amsmath package, so you will need to import that. Also, the reason why it is called dfrac is because it is a \frac that is in display mode, which in general makes things larger.

\documentclass{article}
\usepackage{amsmath}

\begin{document}
Large Fraction: $\dfrac{1}{2}$
Small Fraction: $\frac{1}{2}$
\end{document}


BTW, if you want to do a fraction like "1/2" (with the slash) use \sfrac

• This is already covered, in detail, by all the other answers. – Werner Mar 29 '15 at 13:42