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Use latex math macro

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andrewchengchou

31 May, 2015 05:34 PM

I was trying to define a latex math macro throughout one markdown file. The latex macro is to define a matrix transpose:
\newcommand{\tr}{{\scriptscriptstyle\mathrm{T}}}

I managed to do it by adding the following scripts at the beginning of the markdown file.

<script type="text/x-mathjax-config">
  MathJax.Hub.Config({
  TeX: {
    Macros: {
      tr: "{\scriptscriptstyle\mathrm{T}}",
    }
  }
});
</script>

I can then use the command \tr throughout the markdown file. For example,

<script type="text/x-mathjax-config">
  MathJax.Hub.Config({
  TeX: {
    Macros: {
      tr: "{\scriptscriptstyle\mathrm{T}}",
    }
  }
});
</script>
The tranpose of a real matrix $A$ is denoted by $A^\tr$.

QUESTION: How can I make the above macro as a user default in marked 2 app? So I don't have to copy and paste the scripts for a new markdown document.

1. Support Staff 1 Posted by Brett on 31 May, 2015 06:36 PM

   

   Under Style preferences, you'll see an "Additional MathJax Config"
   field. Add the part of your script that's inside the MathJax.Hub.Config
   object to that field and save:

   TeX: {
        Macros: {
   tr: "{\scriptscriptstyle\mathrm{T}}",
         }
   }

   -Brett

   • Edit

2. Support Staff 2 Posted by Brett on 31 May, 2015 06:36 PM

   

   You may need the include the outer curly brackets around that, I can't
   recall offhand how I have that injected. Let me know if you have issues
   and I can dig back into it.

   -Brett

   • Edit

3. 3 Posted by andrewchengchou on 31 May, 2015 11:23 PM

   

   I tried both
   

   TeX: { 
           Macros: { 
   tr: "{\scriptscriptstyle\mathrm{T}}", 
           } 
   }
   

   and
   

   {
     TeX: {
       Macros: {
         tr: "{\scriptscriptstyle\mathrm{T}}",
       }
     }
   }
   

   Neither works. And there was an error popped out. Error parsing additional mathjax configuration.
   • Edit

4. Support Staff 4 Posted by Brett on 31 May, 2015 11:48 PM

   

   Ok, I dug into it further and I have an error in the parser that
   converts the string in the preferences into a config object for MathJax.
   I'll try to have this worked out for the next update. In the meantime,
   you could use the raw include syntax to put your macros into a separate
   file and include it in documents that need it:

   <<{filename.js}

   Let me know if that helps.

   Thanks,
   Brett

   • Edit

5. 5 Posted by andrewchengchou on 01 Jun, 2015 12:15 AM

   

   Thanks Brett. Including the outer file works well. But there is one minor issue. Instead of saving the original script, I need to modify it slightly.
   ```
   <script type="text/x-mathjax-config">
     MathJax.Hub.Config({
     TeX: {
       Macros: {
         tr: "{\\scriptscriptstyle\\mathrm{T}}",
       }
     }
   });
   </script>
   ```
   Note the double slash (`\\`) rather `\` in front of `scriptscriptstyle` and `mathrm`.

   • Edit

6. Support Staff 6 Posted by Brett on 01 Jun, 2015 01:08 AM

   

   The code in your comment doesn't show a double slash. It's possible that somewhere along the line it's being unescaped, but Marked shouldn't be doing anything to it when using the raw syntax. I'll double check, though.

   • Edit

7. 7 Posted by andrewchengchou on 01 Jun, 2015 03:19 AM

   

   I don't know why. My comment in the raw text form has double slashes. After formatting it in markdown, it became one slash. So I edited the comment so it is displayed in raw text.

   • Edit