TeX/above

Synopsis
\above[dimen]

Description
\above is TeX's more general command for making fractions. Printing a\above 0.5pt b produces the fraction $$a\over b$$ where the separating bar has thickness 0.5pt. Grouping may be required to make sure that not too much is included in the numerator and denominator. A good rule of thumb is to simply put braces around any fraction as in {a\above 0.5pt b} The primitives \over and \atop can be replicated in terms of \above as \over = \above 0.4pt \atop = \above 0pt