Hi,
welcome to the board!
The
stmaryrd documentation writes something about growing delimiters, but only that
\llbracket
and
\rrbracket
are growing delimiters. I guess
\llflor
and
\rrflor
just aren't designed this way and you would need another package.
A simple
minimal working example, just for verifying how it doesn't work, giving the error
! Missing delimiter (. inserted)
:
Code: Select all
\documentclass{article}
\usepackage{stmaryrd}
\begin{document}
\[
\left\llfloor\frac{x}{y}\right\rrfloor
\]
\end{document}
This MWE just shall show, that it's usually good to post some code for explaining problems, so readers can verify the problem and possibly post a fix.
Stefan