I have the tex file of a paper (https://arxiv.org/abs/2006.00841) in which all equations are written in the following format: $$y = a*x+b $$

Equations aren't declared as \begin{equation} and \end{equation} anywhere. Every equation in the paper has a unique equation number, and as I am making this paper part of a 100-page thesis, I would like to reference the equations directly. When I add \label{some_label_name} in front of the $$ formula $$ equation, it only references the entire, chapter, and not just the individual equation. What can I do, other than manually changing all equations in this and all other papers?

  • 1
    Welcome to TeX.SX! I would say you will have to take the only possible way and to replace all the $$ ... $$ by \begin{equation} ... \end{equation}. The unique number you're talking about has been added manually by the authors and cannot be referenced
    – KersouMan
    Jul 6, 2020 at 6:21
  • 1
    Please clarify how the "unique equation numbers" are assigned. Via \tag instructions, maybe? Are the unique equation numbers visible to readers? Please be specific.
    – Mico
    Jul 6, 2020 at 6:35
  • I might be wrong, but that document looks very (plain) TeX-y to me. Equations use $$...$$ and are manually labelled with \eqno. If you want to use portions of the document in a new LaTeX document, it would be a good idea to modify a few things. You would for example turn $$H = \pmatrix{ 0 & A^\dagger \cr A & 0 \cr}. \eqno(1) $$ into \begin{equation}H = \begin{pmatrix} 0 & A^{\dagger} \\ A & 0 \end{pmatrix}.\end{equation} and let LaTeX assign the numbers automatically.
    – moewe
    Jul 6, 2020 at 6:44
  • A regex match might be able to replace them all with environments.
    – Davislor
    Jul 6, 2020 at 7:05
  • 3
    Are you including the paper, perhaps? I don't think so. Just don't take it as a model for writing LaTeX, because it isn't LaTeX.
    – egreg
    Jul 6, 2020 at 7:54


You must log in to answer this question.

Browse other questions tagged .