13

I'm looking how to change the integral symbol.

For example:

\documentclass{article}
\begin{document}
\[\int_a^b f(x) \mathrm{d} dx\]
\end{document}

I want to only change the font of \int to get a \rm\int like \mathrm{d} or can I define a new \rmint using other package, for example arev?

\documentclass{article}
 %define a new command for \rm font of int

\begin{document}
\[\rmint_a^b \]
\end{document}

to get the style of \int is

enter image description here

I have get \rmoint and \rmint by

\DeclareMathSymbol{\rmintop}{\mathop}{rmlargesymbols}{82}
\DeclareMathSymbol{\rmointop}{\mathop}{rmlargesymbols}{72}

but I can not get all of integrals as follows:

enter image description here

Werner
  • 603,163
TeX.pig
  • 497

2 Answers2

14

Here's a "complete" selection of "upright integrals" using the mathdesign fonts, suitably scaled. The part between \makeatletter and \makeatother has been taken from amsmath.sty and edited.

\documentclass{article}
\usepackage{amsmath}

\makeatletter
\def\upintkern@{\mkern-7mu\mathchoice{\mkern-3.5mu}{}{}{}}
\def\upintdots@{\mathchoice{\mkern-4mu\@cdots\mkern-4mu}%
 {{\cdotp}\mkern1.5mu{\cdotp}\mkern1.5mu{\cdotp}}%
 {{\cdotp}\mkern1mu{\cdotp}\mkern1mu{\cdotp}}%
 {{\cdotp}\mkern1mu{\cdotp}\mkern1mu{\cdotp}}}
\newcommand{\upiint}{\DOTSI\protect\UpMultiIntegral{2}}
\newcommand{\upiiint}{\DOTSI\protect\UpMultiIntegral{3}}
\newcommand{\upiiiint}{\DOTSI\protect\UpMultiIntegral{4}}
\newcommand{\upidotsint}{\DOTSI\protect\UpMultiIntegral{0}}
\newcommand{\UpMultiIntegral}[1]{%
  \edef\ints@c{\noexpand\upintop
    \ifnum#1=\z@\noexpand\upintdots@\else\noexpand\upintkern@\fi
    \ifnum#1>\tw@\noexpand\upintop\noexpand\upintkern@\fi
    \ifnum#1>\thr@@\noexpand\upintop\noexpand\upintkern@\fi
    \noexpand\upintop
    \noexpand\ilimits@
  }%
  \futurelet\@let@token\ints@a
}
\makeatother

\DeclareFontFamily{OMX}{mdbch}{}
\DeclareFontShape{OMX}{mdbch}{m}{n}{ <->s * [0.8]  mdbchr7v }{}
\DeclareFontShape{OMX}{mdbch}{b}{n}{ <->s * [0.8]  mdbchb7v }{}
\DeclareFontShape{OMX}{mdbch}{bx}{n}{<->ssub * mdbch/b/n}{}

\DeclareSymbolFont{uplargesymbols}{OMX}{mdbch}{m}{n}
\SetSymbolFont{uplargesymbols}{bold}{OMX}{mdbch}{b}{n}
\DeclareMathSymbol{\upintop}{\mathop}{uplargesymbols}{82}
\DeclareMathSymbol{\upointop}{\mathop}{uplargesymbols}{"48}

\DeclareFontEncoding{MDB}{}{}
\DeclareFontFamily{MDB}{mdbch}{}
\DeclareFontShape{MDB}{mdbch}{m}{n}{ <->s * [0.8]  mdbchrmb }{}
\DeclareFontShape{MDB}{mdbch}{b}{n}{ <->s * [0.8]  mdbchbmb }{}
\DeclareFontShape{MDB}{mdbch}{bx}{n}{<->ssub * mdbch/b/n}{}
\DeclareFontSubstitution{MDB}{cmr}{m}{n}
\DeclareSymbolFont{mathdesignB}{MDB}{mdbch}{m}{n}%
\SetSymbolFont{mathdesignB}{bold}{MDB}{mdbch}{b}{n}%
\DeclareMathSymbol{\upintclockwise}{\mathop}{mathdesignB}{128}
\DeclareMathSymbol{\upointclockwise}{\mathop}{mathdesignB}{130}
\DeclareMathSymbol{\upointctrclockwise}{\mathop}{mathdesignB}{132}
\DeclareMathSymbol{\upoiint}{\mathop}{mathdesignB}{134}
\DeclareMathSymbol{\upoiiint}{\mathop}{mathdesignB}{136}

\makeatletter
\newcommand{\upint}{\DOTSI\upintop\ilimits@}
\newcommand{\upoint}{\DOTSI\upointop\ilimits@}
\makeatother

\begin{document}
$\upint_a^b\quad\int_a^b$ (for size comparison)

$\displaystyle\upint_a^b\quad\int_a^b$ (for size comparison)

$\displaystyle\upint\quad\upiint\quad\upiiint\quad\upidotsint$

$\displaystyle\upointclockwise\quad\upointctrclockwise\quad\upoint\quad\upoiint\quad\upoiiint$
\end{document}

enter image description here

egreg
  • 1,121,712
  • @Manuel Sorry, I introduced a bug with my last edit. Fix in a minute. – egreg Dec 27 '12 at 16:58
  • A new small problem, all the limits work well except in \upiint, \upiiint and (may be) \upidotsint. Try with this code: \upiint_a^b\quad\upiiint_a^b\quad\upidotsint_a^b (if you use \limits the b is not correctly positioned, and if you use \nolimits the a is not correctly positioned. Could you solve this? – Manuel Dec 27 '12 at 17:23
  • Thank you! Can we get it by changing the font of esint package? I have no idea until now. – TeX.pig Dec 28 '12 at 01:31
  • @Manuel When using \limits after multiple integrals only the lower limit makes sense and the code in amsmath is providing a centered lower limits; in my experiment the behavior with \nolimits seems correct. – egreg Dec 28 '12 at 10:48
  • @TeX.pig esint uses its own font, that consists only of integral symbols. – egreg Dec 28 '12 at 10:50
  • @egreg Okey, I don't know why, but the problem comes from using \usepackage[intlimits]{amsmath}. If you load the package with that option and then use \limits or \nolimits it works bad, as I said. – Manuel Dec 28 '12 at 23:04
  • @Manuel As I said, multiple integrals really support only lower limits. – egreg Dec 28 '12 at 23:09
  • @egreg Yes, I agree with that, but WITHOUT inlimits option loaded. If you load it and use \upiiint\nolimits_a^b there is a problem with the sub a. But this is not truly related with the change font question. – Manuel Dec 28 '12 at 23:17
  • @Manuel I see; but I don't see why one should set the intlimits option and use \nolimits for a triple integral. – egreg Dec 28 '12 at 23:23
  • Don't worry, I don't use it. Just wanted to get all right, as with \upoiint and \upoiiint the limits work pretty well. – Manuel Dec 28 '12 at 23:31
12

Define a new math font from a new font family besides the default cmex, for instance, mdbch and euex. Refer to arevmath.sty.

\documentclass{article}
%define a new command for \rm font of int
\DeclareSymbolFont{rmlargesymbols}{OMX}{mdbch}{m}{n}
% or \DeclareSymbolFont{rmlargesymbols}{U}{euex}{m}{n}
\DeclareMathSymbol{\rmintop}{\mathop}{rmlargesymbols}{82}
\newcommand{\rmint}{\rmintop\nolimits}
\begin{document}
$\rmint_a^b$
\[\rmint_a^b \]

\end{document}
Wenbo
  • 346
  • 1
    If you use \DeclareMathSymbol{\intop}..., then \int will give the new symbol without any other intervention. With amsmath one may get wrong spacing with multiple integrals and so may need to modify \intkern@ and \intdots@. – egreg Dec 27 '12 at 11:46
  • I'm trying to get this method to work with a different font, pxfonts. The reason for this is that I need both \int and \boldsymbol{\int} (which is not provided in the default). I don't need multiple integrals.

    I can't understand what "82" is (I cannot even find the symbol \int in mdbch.sty...). Can anyone help me with this? Thank you.

     – Emilio Ferrucci May 03 '21 at 14:28