Support Katex in '.md' files

[Justaphysicsnerd]

Is your feature request related to a problem? Please describe.
I'm always frustrated whenever I open any markdown file, it has lot of lines written in KATEX. We all know that how complicated katex can be in its code form. So when i open my markdown files the katex is still in its code form.

Describe the solution you'd like
Improve the markdown file viewer i.e. add KATEX support to it.

Describe alternatives you've considered
If you don't want to make that permanent, maybe make plugins for KATEX, MathJAX etc.

Additional context
Please

[xupefei]

One question since I haven’t tried to write LaTeX maths in Markdown: which of KATEX and MathJAX is more popular (and more worthy to support)?

[Justaphysicsnerd]

Thanks for the reply. To be quiet honest it depends. People have personal opinion on this. I for one has no problem with either of those, since the Tex written in KaTex works in MathJax as well. But if you are looking for speed then I suggest to use MathJax since it is faster among the two and is also used by sites like stack exchange and Wikipedia

…

________________________________ From: Paddy Xu <[email protected]> Sent: Friday, May 1, 2020 9:45:56 PM To: QL-Win/QuickLook <[email protected]> Cc: Justaphysicsnerd <[email protected]>; Author <[email protected]> Subject: Re: [QL-Win/QuickLook] Support Katex in '.md' files (#639) One question since I haven’t tried to write LaTeX maths in Markdown: which of KATEX and MathJAX is more popular (and more worthy to support)? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub<#639 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APK66AGB5BMV2EEOP5ZQDQ3RPLYTZANCNFSM4MRJSOUQ>.

[xupefei]

Fixed!

[Justaphysicsnerd]

So, is it coming in the next release and please tell me what solution did you implement ?

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________________________________ From: Pengfei Xu <[email protected]> Sent: Saturday, May 16, 2020 11:45:01 PM To: QL-Win/QuickLook <[email protected]> Cc: Justaphysicsnerd <[email protected]>; Author <[email protected]> Subject: Re: [QL-Win/QuickLook] Support Katex in '.md' files (#639) Fixed! — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub<#639 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APK66AAQMJBZU4LD5CAECPLRR3J2LANCNFSM4MRJSOUQ>.

[xupefei]

The new version will be released very soon, and meanwhile, you can get it here: https://ci.appveyor.com/project/xupefei/quicklook/builds/32922024/artifacts

I added MathJax support. You have to connect to the Internet to see equations (MathJax must download some assets to render equations).

[Justaphysicsnerd]

Thanks

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________________________________ From: Pengfei Xu <[email protected]> Sent: Sunday, May 17, 2020 12:22:16 AM To: QL-Win/QuickLook <[email protected]> Cc: Justaphysicsnerd <[email protected]>; Author <[email protected]> Subject: Re: [QL-Win/QuickLook] Support Katex in '.md' files (#639) The new version will be released very soon, and meanwhile, you can get it here: https://ci.appveyor.com/project/xupefei/quicklook/builds/32922024/artifacts I added MathJax support. You have to connect to the Internet to see equations (MathJax must download some assets to render equations). — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub<#639 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APK66AFNGJVYPE3XG37BQSLRR3OGBANCNFSM4MRJSOUQ>.

[Justaphysicsnerd]

I tried the new version but it doesn’t work [cid:[email protected]] Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10

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________________________________ From: Pengfei Xu <[email protected]> Sent: Sunday, May 17, 2020 12:22:16 AM To: QL-Win/QuickLook <[email protected]> Cc: Justaphysicsnerd <[email protected]>; Author <[email protected]> Subject: Re: [QL-Win/QuickLook] Support Katex in '.md' files (#639) The new version will be released very soon, and meanwhile, you can get it here: https://ci.appveyor.com/project/xupefei/quicklook/builds/32922024/artifacts I added MathJax support. You have to connect to the Internet to see equations (MathJax must download some assets to render equations). — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub<#639 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/APK66AFNGJVYPE3XG37BQSLRR3OGBANCNFSM4MRJSOUQ>.

[xupefei]

I can't see your attached image.

[Justaphysicsnerd]

[Image]

[xupefei]

You should post images by using your web browser and go to github.com.

[Justaphysicsnerd]

[Justaphysicsnerd]

it doesn't work, i have installed the latest version. Sorry for the late reply

[xupefei]

Could you upload the MD file here so I can test?

[Justaphysicsnerd]

Github doesn't support uploading markdown files so i am just gonna copy the content of the file
To Convert all the indeterminate forms into the form of $\displaystyle{\frac{0}{0} \text{or} \frac{\infty}{\infty}}$
1)

$\displaystyle{ 0 * \frac{1}{0} ~~\text{or}~~ \frac{1}{\infty}*\infty }$
For example :
$\displaystyle{ \lim_{x \to \frac{\pi}{2}} \sec x (x-\frac{\pi}{2}) }$
$\displaystyle{\Rightarrow \lim_{x \to \frac{\pi}{2}} \frac{x-\frac{\pi}{2}}{\cos x} }$
$\displaystyle{\Rightarrow -\lim_{x \to \frac{\pi}{2}} \frac{(\frac{\pi}{2} - x)}{\sin(\frac{\pi}{2}-x)} }$
$\displaystyle{\Rightarrow \boxed{-1}}$

$$
\begin{cases}
\text{If the function is trignometric :} &\text{convert it in} \sin and \cos ~~\text{For example :} \boxed{\displaystyle{\lim_{x\to\frac{\pi}{2}}(\sec x - \tan x) = \lim_{x\to\frac{\pi}{2}} \frac{1-\sin x}{\cos x} = \lim_{x\to\frac{\pi}{2}} \frac{1-\sin^{2}x}{\cos x(1+\sin x)} =\lim_{x\to\frac{\pi}{2}} \frac{\cos x}{1+\sin x} = 0 }} \\
\text{For any other function :} &\begin{cases} \text{use rationalization ~For example :}\boxed{\displaystyle{\lim_{x\to\infty}(\sqrt{x^{2}-3x+2} - \sqrt{x^{2} + 4x + 2}) = \frac{-7x}{(\sqrt{x^{2}-3x+2} + \sqrt{x^{2} + 4x + 2})} = \frac{-7}{\sqrt{1-\frac{3}{x}+\frac{2}{x^2}} + \sqrt{1 +\frac{4}{x}+\frac{2}{x^{2}} }} = \frac{-7}{2} }} \\
                                               \text{put} ~x~ = \frac{1}{h}
\end{cases}
\end{cases}
$$

[Justaphysicsnerd]

the function text is somehow striken out

[Justaphysicsnerd]

in github

[xupefei]

Thanks. I will test soon.

[xupefei]

I managed to test MathJax and found it does not work in QuickLook. I don't know why this happens, since the same webpage can actually show equations in IE and I have set QL WebBrowser's compatibility version to 11.

I think this issue can't be fixed unless we replace the system WebBrowser (IE) with CefSharp (Chrome). Anyone can help here?

HTML for test: md2html.zip

[Justaphysicsnerd]

Maybe try something like katex ? I am sorry if I am wrong, I am just a student.

[Chaphasilor]

Could KaTeX-support be added as well? Currently it's only partially working:

---

Source:

### Terminology

- For the training samples, each sample is assigned a class $y \in \mathcal{Y} \triangleq \{y_1, ..., y_N\}\,$
- The mean vector for a class $y_i$ is $\boldsymbol{\mu}(y=y_i) \equiv \boldsymbol{\mu}_{y_i}\,$
- The covariance matrix of class $y_i$ is denoted by $\bold{\Sigma}(y=y_i) \equiv \bold{\Sigma}_{y_i}\,$

### Quadratic Discriminant Analysis

Distinguishes between two classes by evaluating
$$
Q(\bold{x}) = \frac{1}{2} \left[ (\bold{x} - \hat{\boldsymbol{\mu}}_2)^T \hat{\bold{\Sigma}}_2^{-1} (\bold{x} - \hat{\boldsymbol{\mu}}_2) - (\bold{x} - \hat{\boldsymbol{\mu}}_1) \hat{\bold{\Sigma}}_1^{-1} (\bold{x} - \hat{\boldsymbol{\mu}}_1) \right] + \frac{1}{2}\log \left( \frac{\left| \hat{\bold{\Sigma}}_2 \right|}{\left| \hat{\bold{\Sigma}}_2 \right|} \right).
$$

- $\bold{x} \in \Reals^p$: a sample from the test data set
- $\hat{\boldsymbol{\mu}}_1, \hat{\boldsymbol{\mu}}_2 \in \Reals^p$ and $\hat{\bold{\Sigma}}_1, \hat{\bold{\Sigma}}_2 \in \Reals^{p \times p}$: location and covariance estimates given the two populations of training data

---

• Inline math ($...$) isn't supported at all, neither are numbered equations ($$...$$ (1))
• Some commands aren't supported in "display" mode ($$...$$):
  • \boldsymbol{} is working, but \bold{} isn't
  • Line breaks (\\ or \ \\) aren't working (causing things like \begin{cases} to not work either, as they require line breaks)
  • Some symbols like \infin (∞) or \rarr (→) aren't working
• Sometimes, even display mode ($$...$$) isn't working for some reason, here is an example:

  # $l_p$-periodogram PSD estimate
  
  $$
  \hat{S}_{yy}(e^{j\omega}) = \frac{N}{4} \left| \boldsymbol{\hat{\beta}}_{l_p}(\omega) \right|^2
  $$

[MrPancakes39]

@Chaphasilor I can't help much but,

Instead of using \bold:

$$
Q(\bold{x}) = \frac{1}{2} \left[ (\bold{x} - \hat{\boldsymbol{\mu}}_2)^T \hat{\bold{\Sigma}}_2^{-1} (\bold{x} - \hat{\boldsymbol{\mu}}_2) - (\bold{x} - \hat{\boldsymbol{\mu}}_1) \hat{\bold{\Sigma}}_1^{-1} (\bold{x} - \hat{\boldsymbol{\mu}}_1) \right] + \frac{1}{2}\log \left( \frac{\left| \hat{\bold{\Sigma}}_2 \right|}{\left| \hat{\bold{\Sigma}}_2 \right|} \right).
$$

Using \boldsymbol seems to work for MathJax:

$$
Q(\boldsymbol{x}) = \frac{1}{2} \left[ (\boldsymbol{x} - \hat{\boldsymbol{\mu}}_2)^T \hat{\boldsymbol{\Sigma}}_2^{-1} (\boldsymbol{x} - \hat{\boldsymbol{\mu}}_2) - (\boldsymbol{x} - \hat{\boldsymbol{\mu}}_1) \hat{\boldsymbol{\Sigma}}_1^{-1} (\boldsymbol{x} - \hat{\boldsymbol{\mu}}_1) \right] + \frac{1}{2}\log \left( \frac{\left| \hat{\boldsymbol{\Sigma}}_2 \right|}{\left| \hat{\boldsymbol{\Sigma}}_2 \right|} \right).
$$

Since QuickLook currently uses MathJax and not KaTeX

[Chaphasilor]

@MrPancakes39 yeah, I already noted that in my comment. The bahavior of \bold{} and \boldsymbol{} is slightly different however, so it isn't a drop-in replacements.
And of course, as I pointed out there are many other problems with KaTeX :)