using \cref{**} for diagrams and equations

Question

Thanks to the answer, which suggested me to use \cref{} to refer sections, definitions etc.

I am using \begin{equation} \end{equation} for both equations and diagrams. So, when I use \cref{}, I am getting Equation (reference number) for diagrams. Is there a way to fix it?

Please find the minimal working example after suggestion of Willie Wong

\documentclass[11pt,twoside]{book}
%%% Packages
% 1. fonts
\usepackage[T1]{fontenc} % recommended
%\usepackage[utf8]{inputenc} % no longer needed
\usepackage{fix-cm} % for Computer Modern (comment if using the next line)
%\usepackage{newpxtext,newpxmath} % for Palatino
%\usepackage{upgreek} % do you need it?
%\usepackage{charter} % it has no support for math
%\usepackage{relsize} % do you need it?
\usepackage{a4wide}
% 2. Math
\usepackage{stmaryrd}
\usepackage{mathrsfs}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{mathtools}
\usepackage{bm}% bold math
\usepackage[normalem]{ulem}
% 3. Graphics and special effects
\usepackage{graphicx}
\usepackage{tikz}
\usetikzlibrary{cd}
\usepackage{tikz-cd}
\usepackage{shadow}% do you need it?
\usepackage{fancybox}% do you need it?
\usepackage{scalerel,stackengine}
\usepackage{eso-pic}
% 4. Document formatting
\usepackage{setspace}
\usepackage{fancyhdr}
\usepackage{appendix}
\usepackage[nottoc]{tocbibind}
\usepackage{alltt}
\usepackage{amsthm}
\usepackage[colorlinks]{hyperref}
\usepackage[nameinlink]{cleveref}
\newcounter{diagram}
\newenvironment{diagram}{\setcounter{diagram}{\value{equation}}\refstepcounter{diagram}}{}
\begin{document}
\pagenumbering{roman}

\include{Title} 

\newpage
\thispagestyle{empty}
\bigskip{}
\vspace{1cm} \cleardoublepage 



\begin{diagram}\label{diagram:diagram}
    \begin{equation}
        \begin{tikzcd}[sep=large]
            A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \\
            & & &       \\
            C \arrow[rrr]  & & & D   
        \end{tikzcd}    
    \end{equation}
\end{diagram}


    \begin{diagram}
    \begin{equation}\label{diagram:diagram1}
        \begin{tikzcd}[sep=large]
            A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \\
            & & &       \\
            C \arrow[rrr]  & & & D   
        \end{tikzcd}    
    \end{equation}
\end{diagram}

\begin{equation}\label{eqn:equation}
    y = mx + c
\end{equation}

\Cref{diagram:diagram}
\Cref{diagram:diagram1}
\Cref{eqn:equation}





\end{document}

Please find attached output

Answer 1

We can define a new diagram environment and make it work with cleveref. I assumed that you want the counter to be the same for both equations and diagrams.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{cd}
\usepackage[colorlinks]{hyperref}
\usepackage[nameinlink]{cleveref}
\newcounter{diagram}  % Create counter for diagrams
% Create diagram environment
\newenvironment{diagram}[1][]{%
    \begin{equation}%
    \begin{tikzcd}[#1]%
    \setcounter{diagram}{\theequation}
    \addtocounter{diagram}{-1}
    \refstepcounter{diagram}
}{%
    \end{tikzcd}%
    \end{equation}%
}
% Add cleveref information for diagram
\crefname{diagram}{diagram}{diagrams}
\crefname{diagram}{Diagram}{Diagrams}
\creflabelformat{diagram}{(#1) #2 #3}
\begin{document}
    \begin{equation}\label{eqn:equation}
        y = mx + c
    \end{equation}
\begin{diagram}[row sep=2cm, column sep=3cm] \label{dia:diagram}
    A \arrow[d] \arrow[r] & B \arrow[d]\\
    C \arrow[r] & D
\end{diagram}
\Cref{eqn:equation} \Cref{dia:diagram}

\end{document}

Explanation

First we define a new counter, diagram. Whenever cleveref 'sees' this counter it will know that we want a diagram label. We then define an environment, diagram. This includes a tikzcd environment inside a equation environment. The equation environment ensures that the numbering and spacing is the same as for equations. Note that any optional arguments passed to the diagram environment are passed on to the tikzcd environment. We then set the counter diagram to be the same value as the equation counter. We then subtract one and then in a single step increment and reference the diagram counter (this is why we needed to subtract one first). By doing this after the equation environment starts we ensure that the \label command 'sees' the diagram counter. We then end the environment by closing the two environments we opened.

To make cleveref work with the diagram environment there are a couple of things we have to do. First we need to tell cleveref what word to use in place of 'Equation', this is done with

\crefname{<type>}{<singular>}{<plural>}

in this case <type> is the counter we are referencing, so diagram and <singular>/<plural> are the singular/plural form of the word. The next line is the same but uses \Crefname which defines the capitalised version of the word. We could get away with defining just upper or just lower case and then cleveref will work out the other version but its simple enough to define both and if the name was more complicated then cleveref may fail to find the correct capitalisation. The final thing we have to do is use

\creflabelformat{<type>}{<format>}

to tell cleveref how to print the label, in this case <type> is the counter diagram again and format is (#1) #2 #3 which puts brackets around the number and the other two have to do with getting hyperref to work with clveref, which can be seen from the red links in the image (simply remove colorlinks from the hyperref options to get rid of the colour).

I've taken the liberty of removing blank lines in the example diagram and instead setting row sep and column sep.

Answer 2

When a counter is printed (in a caption, equation number, or using \ref or \cref) LaTeX uses the internal macro \thecountername for the various counter names, for example \theequation for the equation number and \thechapter for the chapter number.

This macro is the connection between the counter and the output in the document, the counter itself is an internal variable and the macro controls how this variable is printed: in arabic or roman numerals for example, but also if there is any other information added in the printed form, such as the section or chapter number.

When you make a new counter with \newcounter{diagram} then LaTeX automatically creates the macro \thediagram, which is defined by default as \arabic{diagram}, so the arabic number and nothing else. This definition is picked up by \Cref, so only (1) is shown. However, it is possible to redefine \thediagram yourself after you make the counter:

\newcounter{diagram}
\def\thediagram{\thechapter.\arabic{diagram}}

In this definition the chapter counter is printed first, then a period, then the arabic representation of the diagram counter itself. This is very similar to how \theequation is defined by LaTeX itself.

Full MWE:

\documentclass[11pt,twoside]{book}
\usepackage{amsmath}
\usepackage{tikz-cd}
\usepackage[colorlinks]{hyperref}
\usepackage[nameinlink]{cleveref}
\newcounter{diagram}
\def\thediagram{\thechapter.\arabic{diagram}}
\newenvironment{diagram}{\setcounter{diagram}{\value{equation}}\refstepcounter{diagram}}{}
\crefname{diagram}{diagram}{diagrams}
\crefname{diagram}{Diagram}{Diagrams}
\creflabelformat{diagram}{(#1)#2#3}
\begin{document}
\chapter{Diagrams and equations}
\begin{diagram}\label{diagram:diagram}
  \begin{equation}
      \begin{tikzcd}[sep=large]
          A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \
          & & &       \
          C \arrow[rrr]  & & & D

      \end{tikzcd}

  \end{equation}
\end{diagram}
\begin{diagram}
  \begin{equation}\label{diagram:diagram1}
      \begin{tikzcd}[sep=large]
          A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \
          & & &       \
          C \arrow[rrr]  & & & D

      \end{tikzcd}

  \end{equation}
\end{diagram}
\begin{equation}\label{eqn:equation}
  y = mx + c
\end{equation}
\Cref{diagram:diagram}
\Cref{diagram:diagram1}
\Cref{eqn:equation}
\end{document}

Result:

Note that I removed the spaces in the \creflabelformat specification, the spaces were showing in the output.

Answer 3

\documentclass[11pt,twoside]{book}

%%% Packages
% 1. fonts
\usepackage[T1]{fontenc} % recommended
%\usepackage[utf8]{inputenc} % no longer needed
\usepackage{fix-cm} % for Computer Modern (comment if using the next line)
%\usepackage{newpxtext,newpxmath} % for Palatino
%\usepackage{upgreek} % do you need it?
%\usepackage{charter} % it has no support for math
%\usepackage{relsize} % do you need it?
\usepackage{a4wide}
% 2. Math
\usepackage{stmaryrd}
\usepackage{mathrsfs}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{mathtools}
\usepackage{bm}% bold math
\usepackage[normalem]{ulem}
% 3. Graphics and special effects
\usepackage{graphicx}
\usepackage{tikz}
\usetikzlibrary{cd}
\usepackage{tikz-cd}
\usepackage{shadow}% do you need it?
\usepackage{fancybox}% do you need it?
\usepackage{scalerel,stackengine}
\usepackage{eso-pic}

% 4. Document formatting
\usepackage{setspace}
\usepackage{fancyhdr}
\usepackage{appendix}
\usepackage[nottoc]{tocbibind}
\usepackage{alltt}
\usepackage{amsthm}


\usepackage[colorlinks]{hyperref}
\usepackage[nameinlink]{cleveref}

\newcounter{diagram}
\newenvironment{diagram}{\setcounter{diagram}{\value{equation}}\refstepcounter{diagram}}{}

\crefname{diagram}{diagram}{diagrams}
\crefname{diagram}{Diagram}{Diagrams}
\creflabelformat{diagram}{(#1) #2 #3}

\begin{document}

    \pagenumbering{roman}

    \include{Title} 

    \newpage
    \thispagestyle{empty}
    \bigskip{}
    \vspace{1cm} \cleardoublepage 

    \chapter{chapter 1}

    \begin{diagram}\label{diagram:diagram}
        \begin{equation}
            \begin{tikzcd}[sep=large]
                A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \\
                & & &       \\
                C \arrow[rrr]  & & & D   
            \end{tikzcd}    
        \end{equation}
    \end{diagram}


    \begin{diagram}
        \begin{equation}\label{diagram:diagram1}
            \begin{tikzcd}[sep=large]
                A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \\
                & & &       \\
                C \arrow[rrr]  & & & D   
            \end{tikzcd}    
        \end{equation}
    \end{diagram}

    \begin{equation}\label{eqn:equation}
        y = mx + c
    \end{equation}

    \Cref{diagram:diagram}
    \Cref{diagram:diagram1}
    \Cref{eqn:equation}


\end{document}

Diagram (reference number) is coming, but, it is not taking chapter/section number. Please see the attached photo.

Is there a way to get chapter/section number?

Answer 4

Correct if I got anything wrong, because to me the request sounds weird. You want the label to always refer to the number of the diagram, even if you have nested numbered elements?

Because this would simply lead me to \let\refstepcounter\stepcounter within the environment. But I'd still suggest to then create an environment which is already nesting the equation and use \tag so the equation is accessing the diagram counter instead of the equation counter.

Full example would be…

\documentclass[11pt,twoside]{book}
\usepackage[T1]{fontenc} % recommended
\usepackage{amsmath}
\usepackage{tikz-cd}
\usepackage[colorlinks]{hyperref}
\usepackage[nameinlink]{cleveref}
%as posted by Willoughby which I wouldn't do different
% Add cleveref information for diagram
\crefname{diagram}{diagram}{diagrams}
\crefname{diagram}{Diagram}{Diagrams}
\creflabelformat{diagram}{(#1) #2 #3}
\newcounter{diagram}
\newenvironment{diagram}{\setcounter{diagram}{\value{equation}}\refstepcounter{diagram}%
    %let all labels within diagram be set to the diagram counter
    \let\refstepcounter\stepcounter
}{}
\renewcommand{\thediagram}{\thesection.\arabic{diagram}}% or replace \thesection by \thechapter
%or if you don't want to use the chapter
%\renewcommand{\thediagram}{\arabic{section}.\arabic{diagram}}
%add resetcounter to equation
\makeatletter
@addtoreset{equation}{section}% might be replaced by chapter
\renewcommand{\theequation}{\thesection.\arabic{equation}}% might be replaced by \thechapter
\makeatother
\begin{document}
    \chapter{to have a chapter number}
    \section{to have a section number}
    \begin{diagram}\label{diagram:diagram}
        \begin{equation}
            \begin{tikzcd}[sep=large]
                A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \
                & & &       \
                C \arrow[rrr]  & & & D

            \end{tikzcd}

        \end{equation}
    \end{diagram}
\begin{diagram}
    \begin{equation}\label{diagram:diagram1}
        \begin{tikzcd}[sep=large]
            A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \\
            & & &       \\
            C \arrow[rrr]  & & & D   
        \end{tikzcd}    
    \end{equation}
\end{diagram}

\begin{equation}\label{eqn:equation}
    y = mx + c
\end{equation}

\Cref{diagram:diagram}
\Cref{diagram:diagram1}
\Cref{eqn:equation}

\chapter{to have a chapter number}
\section{to have a section number}
\begin{diagram}\label{diagram:diagram}
    \begin{equation}
        \begin{tikzcd}[sep=large]
            A \arrow[dd] \arrow[rrr]  & & & B \arrow[dd] \\
            & & &       \\
            C \arrow[rrr]  & & & D   
        \end{tikzcd}    
    \end{equation}
\end{diagram}





\end{document}