[Tex/LaTex] Big floor symbols

symbols

When I write

\lfloor\dfrac{1}{2}\rfloor

the floors come out too short to cover the fraction. How can I lengthen the floor symbols?

Best Answer

You could use \left...\right for stretchable delimiters, or perhaps one of the pairs of the \bigl...\bigr family of commands:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\[
\Bigl\lfloor\dfrac{1}{2}\Bigr\rfloor\qquad
\left\lfloor\dfrac{1}{2}\right\rfloor
\]

\end{document}

enter image description here

Related Solutions

[Tex/LaTex] The line produced by \not looks bad on wider symbols

The \not symbol typesets a zero width character which protrudes on the right and so it is apt to be superimposed only on certain characters having a suitable width (the equal sign, for example); since the two arrows are wider than the equal sign, the alignment is not optimal. A solution is to push the \not a bit on the right and backspacing for the same amount:

\newcommand\nleftrightarrow{
  \mathrel{\mkern2.1mu\not\mkern-2.1mu\leftrightarrow}}
\newcommand\nLeftrightarrow{
  \mathrel{\mkern2.1mu\not\mkern-2.1mu\Leftrightarrow}}

You might also consider the set of "negated arrows" provided by amssymb; the names are the same that I chose:

\usepackage{amssymb}

$X\nleftrightarrow Y$ and $X\nLeftrightarrow Y$

Try both and choose what suits your taste. If you already load amssymb use \renewcommand instead of \newcommand.

enter image description here

One can also define a \xnot command that gives to the symbol the width of the equal sign and use a standard method for superimposing symbols:

\newcommand\xnot{\mathpalette\xxnot}
\newcommand*\xxnot[2]{\mathrel{\ooalign{%
  \hfil$#1\not\mathrel{\hphantom=}$\hfil\cr\hfil$#1#2$\hfil\cr}}}

Now \xnot\leftrightarrow gives the same result as the "definition by hand" before. The strange \mathrel after \not has its explanation in the fact that TeX never adds space between two relation math atoms. Thanks to Martin for having suggested this method. The centernot package does something similar.

[Tex/LaTex] How to horizontally merge two symbols

For this problem the solution is quite simple:

\mathrel{+}=

so that the combination will be treated as a relation, since = is a relation and TeX never puts space between two relation symbols. So

$a \mathrel{+}= b$

will be rendered as

enter image description here

You might want to define a shorthand

\newcommand{\pluseq}{\mathrel{+}=}

and input the formula above as

$a \pluseq b$

Best Answer

Related Solutions

[Tex/LaTex] The line produced by \not looks bad on wider symbols

[Tex/LaTex] How to horizontally merge two symbols

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