Problem with math equations

[PascP]

Hello,

I've tried to make an epub from a website using calibre so I can read it offline. The website containts a lot of math and equations. Now, my problem is that calibre shows some of the math but not all of them, and i dont mean that it shows them twisted or unformated but not at all. Also when i press F5 to refresh the ebook the reader displays "Typesetting Math" and loads from 0% to 100%. at around 20-50% the math types are beeing displayed but when it reaches 100% they disapear again. I have included below some text with math equations. the first usualy works and the second usualy doesnt get displayed.

<p>Now we can define <span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>h</mi><mi mathvariant="italic">θ</mi></msub><mo stretchy="false">(</mo><mi>X</mi><mo stretchy="false">)</mo></math></span><script id="MathJax-Element-18" type="math/tex">h_\theta(X)</script> as a row vector that gives the value of <span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>h</mi><mi mathvariant="italic">θ</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></math></span><script id="MathJax-Element-19" type="math/tex">h_\theta(x)</script> at each of the <span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>m</mi></math></span><script id="MathJax-Element-20" type="math/tex">m</script> training examples:</p>
<p><span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mtable minlabelspacing=".8em" side="right" displaystyle="true" columnspacing="0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em" rowspacing="3pt" columnalign="right left right left right left right left right left right left"><mtr><mtd><msub><mi>h</mi><mi mathvariant="italic">θ</mi></msub><mo stretchy="false">(</mo><mi>X</mi><mo stretchy="false">)</mo><mo stretchy="false">=</mo><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msub><mi mathvariant="italic">θ</mi><mn>0</mn></msub><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup><mo stretchy="false">+</mo><msub><mi mathvariant="italic">θ</mi><mn>1</mn></msub><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup><mo stretchy="false">+</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo stretchy="false">+</mo><msub><mi mathvariant="italic">θ</mi><mi>n</mi></msub><msubsup><mi>x</mi><mi>n</mi><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="3em"/><msub><mi mathvariant="italic">θ</mi><mn>0</mn></msub><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup><mo stretchy="false">+</mo><msub><mi mathvariant="italic">θ</mi><mn>1</mn></msub><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup><mo stretchy="false">+</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo stretchy="false">+</mo><msub><mi mathvariant="italic">θ</mi><mi>n</mi></msub><msubsup><mi>x</mi><mi>n</mi><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="3em"/><mo>.</mo><mo>.</mo><mo>.</mo><mspace width="3em"/><msub><mi mathvariant="italic">θ</mi><mn>0</mn></msub><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mi>m</mi><mo stretchy="false">)</mo></mrow></msubsup><mo stretchy="false">+</mo><msub><mi mathvariant="italic">θ</mi><mn>1</mn></msub><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mi>m</mi><mo stretchy="false">)</mo></mrow></msubsup><mo stretchy="false">+</mo><mo>.</mo><mo>.</mo><mo>.</mo><mo stretchy="false">+</mo><msub><mi mathvariant="italic">θ</mi><mi>n</mi></msub><msubsup><mi>x</mi><mi>n</mi><mrow><mo stretchy="false">(</mo><mi>m</mi><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr></mtable></mfenced></mtd></mtr></mtable></math></span><script id="MathJax-Element-21" type="math/tex">
\begin{align*}
h_\theta(X) =
\begin{bmatrix}
\theta_0 x^{(1)}_0 + \theta_1 x^{(1)}_1 + ... + \theta_n x^{(1)}_n \hspace{3em}
\theta_0 x^{(2)}_0 + \theta_1 x^{(2)}_1 + ... + \theta_n x^{(2)}_n \hspace{3em} ... \hspace{3em}
\theta_0  x^{(m)}_0 + \theta_1 x^{(m)}_1 + ... + \theta_n x^{(m)}_n \newline
\end{bmatrix}
\end{align*}
</script></p>
<p>But again using the definition of matrix multiplication, we can represent this more concisely:</p>
<p><span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mtable minlabelspacing=".8em" side="right" displaystyle="true" columnspacing="0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em" rowspacing="3pt" columnalign="right left right left right left right left right left right left"><mtr><mtd><msub><mi>h</mi><mi mathvariant="italic">θ</mi></msub><mo stretchy="false">(</mo><mi>X</mi><mo stretchy="false">)</mo><mo stretchy="false">=</mo><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msub><mi mathvariant="italic">θ</mi><mn>0</mn></msub><mspace width="2em"/><msub><mi mathvariant="italic">θ</mi><mn>1</mn></msub><mspace width="2em"/><mo>.</mo><mo>.</mo><mo>.</mo><mspace width="2em"/><msub><mi mathvariant="italic">θ</mi><mi>n</mi></msub></mtd></mtr></mtable></mfenced><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="2em"/><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="2em"/><mo>.</mo><mo>.</mo><mo>.</mo><mspace width="2em"/><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mi>m</mi><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr><mtr><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="2em"/><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="2em"/><mo>.</mo><mo>.</mo><mo>.</mo><mspace width="2em"/><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mi>m</mi><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr><mtr><mtd><mo stretchy="false">⋮</mo></mtd></mtr><mtr><mtd><msubsup><mi>x</mi><mi>n</mi><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="2em"/><msubsup><mi>x</mi><mi>n</mi><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup><mspace width="2em"/><mo>.</mo><mo>.</mo><mo>.</mo><mspace width="2em"/><msubsup><mi>x</mi><mi>n</mi><mrow><mo stretchy="false">(</mo><mi>m</mi><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr></mtable></mfenced><mo stretchy="false">=</mo><msup><mi mathvariant="italic">θ</mi><mi>T</mi></msup><mi>X</mi></mtd></mtr></mtable></math></span><script id="MathJax-Element-22" type="math/tex">
\begin{align*}
h_\theta(X) =
\begin{bmatrix}
\theta_0 \hspace{2em}  \theta_1 \hspace{2em} ... \hspace{2em} \theta_n
\end{bmatrix}
\begin{bmatrix}
x^{(1)}_0 \hspace{2em} x^{(2)}_0\hspace{2em}  ... \hspace{2em} x^{(m)}_0 \newline
x^{(1)}_1 \hspace{2em} x^{(2)}_1 \hspace{2em} ... \hspace{2em} x^{(m)}_1 \newline
\vdots \newline
x^{(1)}_n \hspace{2em} x^{(2)}_n \hspace{2em} ... \hspace{2em} x^{(m)}_n \newline
\end{bmatrix}=
\theta^T X
\end{align*} 
</script></p>
<p><strong>Note</strong>: this version of the hypothesis function assumes the matrix <span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>X</mi></math></span><script id="MathJax-Element-23" type="math/tex">X</script> and vector <span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi mathvariant="italic">θ</mi></math></span><script id="MathJax-Element-24" type="math/tex">\theta</script> store their values as follows:</p>
<p><span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mtable minlabelspacing=".8em" side="right" displaystyle="true" columnspacing="0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em" rowspacing="3pt" columnalign="right left right left right left right left right left right left"><mtr><mtd><mi>X</mi><mo stretchy="false">=</mo><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr><mtr><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr></mtable></mfenced></mtd><mtd><mo stretchy="false">,</mo><mi mathvariant="italic">θ</mi><mo stretchy="false">=</mo><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msub><mi mathvariant="italic">θ</mi><mn>0</mn></msub></mtd></mtr><mtr><mtd><msub><mi mathvariant="italic">θ</mi><mn>1</mn></msub></mtd></mtr></mtable></mfenced></mtd></mtr></mtable></math></span><script id="MathJax-Element-25" type="math/tex">
\begin{align*}
X = 
\begin{bmatrix}
x^{(1)}_0  x^{(2)}_0  x^{(3)}_0  \newline
x^{(1)}_1  x^{(2)}_1  x^{(3)}_1 
\end{bmatrix}

,\theta = 
\begin{bmatrix}
\theta_0 \newline
\theta_1 \newline
\end{bmatrix}
\end{align*}
</script></p>
<p>You might instead store the training examples in <span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>X</mi></math></span><script id="MathJax-Element-26" type="math/tex">X</script> row-wise, like such:</p>
<p><span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mtable minlabelspacing=".8em" side="right" displaystyle="true" columnspacing="0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em" rowspacing="3pt" columnalign="right left right left right left right left right left right left"><mtr><mtd><mi>X</mi><mo stretchy="false">=</mo><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>1</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr><mtr><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>2</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr><mtr><mtd><msubsup><mi>x</mi><mn>0</mn><mrow><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd><mtd><msubsup><mi>x</mi><mn>1</mn><mrow><mo stretchy="false">(</mo><mn>3</mn><mo stretchy="false">)</mo></mrow></msubsup></mtd></mtr></mtable></mfenced></mtd><mtd><mo stretchy="false">,</mo><mi mathvariant="italic">θ</mi><mo stretchy="false">=</mo><mfenced close="]" open="["><mtable columnspacing="1em" rowspacing="4pt" columnalign="center"><mtr><mtd><msub><mi mathvariant="italic">θ</mi><mn>0</mn></msub></mtd></mtr><mtr><mtd><msub><mi mathvariant="italic">θ</mi><mn>1</mn></msub></mtd></mtr></mtable></mfenced></mtd></mtr></mtable></math></span><script id="MathJax-Element-27" type="math/tex">
\begin{align*}
X = 
\begin{bmatrix}
x^{(1)}_0  x^{(1)}_1  \newline
x^{(2)}_0  x^{(2)}_1  \newline
x^{(3)}_0  x^{(3)}_1 
\end{bmatrix}

,\theta = 
\begin{bmatrix}
\theta_0 \newline
\theta_1 \newline
\end{bmatrix}
\end{align*}
</script></p>

<h2 id="uKMKRwShqcolDYwBCCqBGWG"> <span class="mw-headline" id="Hypothesis_Representation">Hypothesis Representation</span></h2>
<p>Our hypothesis should satisfy:</p>
<p><span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="1.2em"><mn>0</mn><mo stretchy="false">≤</mo><msub><mi>h</mi><mi mathvariant="italic">θ</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo><mo stretchy="false">≤</mo><mn>1</mn></mstyle></math></span><script id="MathJax-Element-4" type="math/tex">
\large
0 \leq h_\theta (x) \leq 1
</script></p>
<p>Our new form uses the "Sigmoid Function," also called the "Logistic Function":</p>
<p><span style="display: none;" class="MathJax_Preview"></span><span style="font-size: 100%;" class="MathJax_MathML"><math xmlns="http://www.w3.org/1998/Math/MathML"><mstyle mathsize="1.2em"><mtable minlabelspacing=".8em" side="right" displaystyle="true" columnspacing="0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em 2em 0.2777777777777778em" rowspacing="3pt" columnalign="right left right left right left right left right left right left"><mtr><mtd/><mtd><msub><mi>h</mi><mi mathvariant="italic">θ</mi></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo><mo stretchy="false">=</mo><mi>g</mi><mo stretchy="false">(</mo><msup><mi mathvariant="italic">θ</mi><mi>T</mi></msup><mi>x</mi><mo stretchy="false">)</mo></mtd></mtr><mtr><mtd/></mtr><mtr><mtd/><mtd><mi>z</mi><mo stretchy="false">=</mo><msup><mi mathvariant="italic">θ</mi><mi>T</mi></msup><mi>x</mi></mtd></mtr><mtr><mtd/><mtd><mi>g</mi><mo stretchy="false">(</mo><mi>z</mi><mo stretchy="false">)</mo><mo stretchy="false">=</mo><mstyle displaystyle="true" scriptlevel="0"><mfrac><mn>1</mn><mrow><mn>1</mn><mo stretchy="false">+</mo><msup><mi>e</mi><mrow><mo stretchy="false">−</mo><mi>z</mi></mrow></msup></mrow></mfrac></mstyle></mtd></mtr></mtable></mstyle></math></span><script id="MathJax-Element-5" type="math/tex">
\large
\begin{align*}
 h_\theta (x) =  g ( \theta^T x ) \newline \newline
 z = \theta^T x \newline
 g(z) = \dfrac{1}{1 + e^{-z}}
\end{align*}
</script></p>

Do you guys have any idea why is this happening? Thank you!!!

[kovidgoyal]

I doubt very much you'll be able to directly take a website with math and get it to render correctly in the viewer. It depends very much on how mathjax is called, what css is used what output jax is used, etc. And looking at the html extract you posted its looks like the postprocessed output from mathjax, not the original markup, which is even less likely to work.

Your best bet is using either mathml for embedded latex/asciimath ina simple html page, like the example here: https://manual.calibre-ebook.com/typesetting_math.html

[PascP]

Hello, thank you for your reply and for the great software .
So do you suggest that the best solution would be to rewrite all the equations in the format used in the link? it will take a long time... I suspected that the format I used was the problem but I cant understand why some equations get displayed and others don't, as well as why even thought the are visible for a sort time then they disappear

[paulKwanlunique]

Originally Posted by kovidgoyal

Your best bet is using either mathml for embedded latex/asciimath ina simple html page, like the example here: https://manual.calibre-ebook.com/typesetting_math.html

ThX you for tips