Context: How to mark up equation solving

[samimaattaCelia]

There should be a context section on how to mark up equation solving. Basically how to mark up the math and commentary parts. I will later submit an example of mark up that I was thinking.

[Lisahartun]

I would love to see an example.
I've found something on the web. What do we think about that?

<math display="block" xmlns="http://www.w3.org/1998/Math/MathML" id="schrodinger">
    <mi title='Imaginary Unit'>i</mi>
    <mi title="Reduced Plank's Constant">ℏ</mi>
    <mfrac title="Partial Differential Operator">
        <mo>∂</mo>
        <mrow>
            <mo>∂</mo>
            <mi title="Time">t</mi>
        </mrow>
    </mfrac>
    <mn title="Wavefunction">Ψ</mn>
    <mo form="infix">=</mo>
    <mfrac>
        <mrow>
            <mo form="infix" lucida="true">-</mo>
            <msup>
                <mi title="Plank's constant">h</mi>
                <mn>2</mn>
            </msup>
        </mrow>
        <mrow>
            <mn>2</mn>
            <mi title="Mass of particle">m</mi>
        </mrow>
    </mfrac>
    <msup title="Laplacian">
        <mo>∇</mo>
        <mn>2</mn>
    </msup>
    <mn title="Wavefunction">Ψ</mn>
    <mo form="infix">+</mo>
    <mi title="Potential energy">V</mi>
    <mn title="Wavefunction">Ψ</mn>
</math>

[samimaattaCelia]

This is how I would approach the equation solving mark up and commentary. This is a pretty common way in Finnish textbooks to show what has been done in the solving process:

The equation solving is arranged in a table and different parts are table cells. That's how they line up nicely with each other. This is also how MathCAT would navigate between the different parts of the equations.

The commentary part is weird, and I don't really know how it should be marked up. I did it like this:
<mo>|</mo><mo>|</mo><mo>:</mo><mn>2</mn> <mtext>(both sides divided by 2)</mtext>. If marked up with <mo>||</mo> MathCAT would read: "parallel (lines)".

This example is from MathCAT's tests, so Neil made it himself. In that sense I trust that it's as intended in the MathML specs as well. I included the mark up for the commentary myself.

Complete mark up:

<math>
          <mrow>
            <mtable>
              <mtr>
                <mtd>
                  <mrow>
                    <mi>x</mi>
                    <mo>+</mo>
                    <mi>y</mi>
                  </mrow>
                </mtd>
                <mtd>
                  <mo>=</mo>
                </mtd>
                <mtd>
                  <mn>7</mn>
                </mtd>
                <mtd>
                  <mo>|</mo><mo>|</mo><mo>:</mo><mn>2</mn> <mtext>(both sides divided by 2)</mtext>
                </mtd>
              </mtr>
              <mtr>
                <mtd>
                  <mfrac>
                  <mrow>
                    <mn>2</mn>
                    <mi>x</mi>
                    <mo>+</mo>
                    <mn>3</mn>
                    <mi>y</mi>
                  </mrow>
                <mn>2</mn>
                </mfrac>
                
                </mtd>
                <mtd>
                  <mo>=</mo>
                </mtd>
                <mtd>
                  <mrow>
                    <mfrac>
                    <mn>17</mn>
                    <mn>2</mn>
                  </mfrac>
                  </mrow>
                </mtd>
                <mtd></mtd>
              </mtr>
            </mtable>
          </mrow>
        </math>