I have a xhtml file(using MathML to present definite integrals). In the xhtml file, there have some dummy variables. Now, I want to using Twig to replace those dummy variables.
integrals.xhtml： 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">
  <mml:mstyle mathsize="1em" displaystyle="true" mathcolor="#0000ff" f
+ontfamily="serif">
    <mml:mrow>
      <mml:msubsup>
        <mml:mstyle displaystyle="true">
          <mml:mo>&#x222b;</mml:mo>
        </mml:mstyle>
        <mml:mn>0</mml:mn>
        <mml:mn>4</mml:mn>
      </mml:msubsup>
    </mml:mrow>
    <mml:msqrt>
      <mml:mrow>
        <mml:mrow>
          <mml:msup>
            <mml:mi>s</mml:mi>
            <mml:mn>2</mml:mn>
          </mml:msup>
        </mml:mrow>
        <mml:mo>+</mml:mo>
        <mml:mi>s</mml:mi>
      </mml:mrow>
      <mml:mspace width="0em" height="1.2ex" />
    </mml:msqrt>
    <mml:mo maxsize="1">(</mml:mo>
    <mml:mn>2</mml:mn>
    <mml:mi>s</mml:mi>
    <mml:mo>+</mml:mo>
    <mml:mn>1</mml:mn>
    <mml:mo maxsize="1">)</mml:mo>
    <mml:mspace width="0.167em" />
    <mml:mi>d</mml:mi>
    <mml:mi>s</mml:mi>
  </mml:mstyle>
</mml:math>

[download]
First, I need to find the value? 
<mml:mi>s</mml:mi>

[download]
Does anyone know an easy way to do this?

In reply to Replace MathML content using Twig by renovatio

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