16.6.3 \mathstrut

Synopsis:

\mathstrut

The analogue of \strut for mathematics. See \strut.

The input $\sqrt{x} + \sqrt{x^i}$ gives output where the second radical is taller than the first. To add extra vertical space without any horizontal space, so that the two have the same height, use $\sqrt{x\mathstrut} + \sqrt{x^i\mathstrut}$.

The \mathstrut command adds the vertical height of an open parenthesis, (, but no horizontal space. It is defined as \vphantom{(}, so see \phantom & \vphantom & \hphantom for more. An advantage over \strut is that \mathstrut adds no depth, which is often the right thing for formulas. Using the height of an open parenthesis is just a convention; for complete control over the amount of space, use \rule with a width of zero. See \rule.


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