# Different \mathcal{J}

For my book I would like a specific symbol for "J" with a glyphs on the head as shown in the following images:

1. First image:

1. Second image:

Exist, peraphs, a command or a fine macro to obtain a similar shape?

Now I'm using now the packages times from https://ctan.org/pkg/times and mtpro2 v. lite https://ctan.org/pkg/mtp2lite and the classical calligraphic fonts using the command \mathcal{J}.

I would like that the symbol has the same size as the \mathcal{T} with the options normal, the slanted (inclined) and the bold character.

I often use \boldsymbol{...} command and I compile my file .tex only with pdfLaTeX.

Thanks to everybody for your precious help.

• This symbol rather resembles a T for me.
– bmv
Apr 23 '18 at 11:45
• Please give a screenshot for your 'J' but not your handwriting for it. Apr 23 '18 at 12:20
• what do you mean by it doesn't exist? If you see some publication take a photograph and upload that, but as I say I think it is better to use a J, isn't it the same J as physics.stackexchange.com/questions/254442/… Apr 23 '18 at 12:24
• then you are just asking about finding a font to match your professor's handwriting !!! why would you want to do that? Apr 23 '18 at 12:38
• sorry but it makes no sense to do that you could include an image of a handwritten j but it makes the digital form far less useful. It is a J just choose a font for the whole document do not chose the look of each letter separately. Apr 23 '18 at 12:41

If you really want a J with a T head :

• By using adjusbox you can cut out the J bottom and the T head. For example: \def\hJ{\clipbox{0 -0.05ex 0 0.1em}{$J$}} \def\hT{\raisebox{0.45em}{\clipbox{0 0.45em 0 0em}{$T$}}}
• You combine them with the suitable \mkern. Using the mathllap command from mathtools package : $\mathllap{\hT}\mkern-15mu\hJ$ gies the desired symbol (mathtalic)

To get the bold or upright version you will have to adjust the kerning because the width is different. And for boldface you will not be able to use \bm but will return to the old \boldmath put in another box. A compromise would be to pass the kern amount as a parameter :

\newcommand\JJ[1][15]{\hT\mkern -#1mu\hJ}
\newcommand\JJbf{\mbox{\boldmath$\JJ[14.2]$}}

$\JJ : \square \mathbf{A} = \mu_0 \,\JJbf$


produces the picture below.

The makeshift (not a real solution) suggested here should work with any font instead of the default latin modern I used in the first picture. If you want to use another (math)font you simply would have to find the correct kerning, which is font dependent. For the other variants (bold, upright etc.), simply add \mathrm or \mathbf or whatever needed in the definitions of \hT and \hJ (inside the \clipbox)
To get the result in the four mathstyles you will have to use \mathchoice, explained in several post on this forum. Here is a full MWE using times and mtpro2 lite, and the result:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{newtxtext}
\usepackage[lite,mtphbi]{mtpro2}
\usepackage[scaled=0.92]{helvet}
\usepackage{amsmath,amssymb}

\def\hJ{\mathchoice%
{\clipbox{0 -0.05ex 0 0.1ex}{$J$}}%
{\clipbox{0 -0.05ex 0 0.1ex}{$J$}}%
{\clipbox{0 -0.05ex 0 0.1ex}{$\scriptstyle J$}}%
{\clipbox{0 -0.05ex 0 0.1ex}{$\scriptscriptstyle J$}}%
}
\def\hT{\mathchoice%
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$T$}}}
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$T$}}}
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$\scriptstyle T$}}}
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$\scriptscriptstyle T$}}}
}

\def\hJbf{\mathchoice%
{\clipbox{0 -0.05ex 0 0.1}{$\mathbf{J}$}}%
{\clipbox{0 -0.05ex 0 0.1}{$\mathbf{J}$}}%
{\clipbox{0 -0.05ex 0 0.1}{$\scriptstyle \mathbf{J}$}}%
{\clipbox{0 -0.05ex 0 0.1}{$\scriptscriptstyle \mathbf{J}$}}%
}
\def\hTbf{\mathchoice%
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$\mathbf{T}$}}}
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$\mathbf{T}$}}}
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$\scriptstyle \mathbf{T}$}}}
{\raisebox{0.45ex}{\clipbox{0 0.45ex 0 0}{$\scriptscriptstyle \mathbf{T}$}}}
}

\newcommand\JJ[1][15.2]{\hT\mkern -#1mu\hJ}
\newcommand\JJbf[1][11.5]{\hTbf\mkern -#1mu\hJbf}

\begin{document}
\huge
A big regular J : $J\quad \mathrm{J}\quad \mathbf{J}$\par
A big regular T : $T\quad \mathrm{T}\quad \mathbf{T}$

This is custom J : $\JJ \quad \square \mathbf{A} = \mu_0 \,\JJbf$

$\JJbf_{\JJ_{\JJ}}$
\end{document}


• I greatly appreciated your answer and voted for it positively. I like it but I would like to have the character that approaches the font times, normal style, that it is more vertical, like bold. For the inclined is fine. For my opinion my question has been misunderstood and it has been voted not appropriately. Apr 23 '18 at 21:18
• I updated my answer with complete example using times and mtpro2, with option mtphbi. Should work with any.
– Jhor
Apr 24 '18 at 12:38
• You are very good and excellent answer. My question is not very bad. I check for your +15. Wonderful. Apr 24 '18 at 20:13
• @egreg Hi. I have tried your code of this morning. I agree with you is not very nice to see. The user response has been exceptional. Apr 24 '18 at 20:16

With mathalfa you can select from a large number of fonts. See What are all the font styles I can use in math mode?.

A symbol similar to yours is here.

\documentclass{article}
\usepackage[cal=pxtx]{mathalfa}
\begin{document}
$\mathcal{J}$
\end{document}


If it's not appropriate, check the table in Christian's answer for the aforementioned question.

• How about something using \ooalign by combining a T with a J? Apr 23 '18 at 14:20