How to define your own shorter command in place of the default longer command?

Question

I would like to not type $\mathbf{\hat{x}}$ every time I want a bold x with a hat over it. I've used \def successfully for other things, but with this I am not sure how to properly use \def or \newcommand in order for me to just type \bhat{x} and have it bold the input letter (whatever that may be - could be an x, y, z, etc.).

I've tried this, but it does not work:

\newcommand{\mathbf{\hat{}}}[1][1]{\bhat} % or...
\def\bhat{{\mbox{$\hat \mathbf{}$}}}

Ambika Vanchinathan · Accepted Answer · 2016-10-28T05:43:29.583

6

Hope this is what you want:

\documentclass{article}
\newcommand\bhat[1]{\ensuremath{\hat{\mathbf{#1}}}}
\begin{document}
some text $\bhat{x}$ or \bhat{y} 
\end{document}

Output:

edited Oct 28 '16 at 05:43

answered Oct 28 '16 at 05:26

Ambika Vanchinathan

2,975

Why not using \ensuremath if the new command is used in a mathematical environment $...\bhat{x}...$ ?
I would suggest \newcommand{\bhat}[1]{\ensuremath{\hat{\mathbf{#1}}}}, then you do not need to put the \bhat command between dollars.
– Jérôme Dequeker Oct 28 '16 at 05:28
1

Relevant: When not to use \ensuremath for math macro? – Werner Oct 28 '16 at 05:33
@JérômeDequeker: Edited to add \ensuremath – Ambika Vanchinathan Oct 28 '16 at 05:35
@Werner: Thanks for the link. I think in this kind of usage, the argument in the \bhat command is only a letter, but thank you to notice we should not put dollars in the arguments. – Jérôme Dequeker Oct 28 '16 at 05:52
Has the hat to be bold too ? If Yes, @AmbikaVanchinathan knows what to edit in the answer. – Jérôme Dequeker Oct 28 '16 at 05:54
@magnetar: Please swap the hat and mathbf in the definition, if the hat needs to be in bold too. – Ambika Vanchinathan Oct 28 '16 at 06:19
@AmbikaVanchinathan Swapping the commands will not make the hat bold. You shouldn't have added \ensuremath. – egreg Oct 28 '16 at 06:40
This worked beautifully, thanks! I tested this within and out of math environments, as well as in-line with regular text with and without dollar signs around it and it all works. – magnetar Oct 28 '16 at 07:29

score 0 · Answer 2 · answered Oct 28 '16 at 06:47

0

\def \hope#1{\bf{\hat{#1}}} \begin{document} This is $\hope{V}$ \end{document}% this works for me. You can use any term inside curly bracket where V is added. It gives proper result.

answered Oct 28 '16 at 06:47

vaman

81

3

The command \bf has been deprecated more than 20 years ago. And no, this doesn't give proper results, because $\hope{V}W$ will make bold also the W. – egreg Oct 28 '16 at 06:53

How to define your own shorter command in place of the default longer command?

2 Answers2