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how do i get the sigmas out of the livescript display?

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Philipp Rupp
Philipp Rupp on 10 Feb 2021
Commented: Philipp Rupp on 22 Feb 2021
Hi Everyone,
I am currently working with a very long equation. And when I output it in the livescript, MATLAB finds several sigmas (see screenshot). I would like to have this equation with the sigmas in order to process it in another function.
So far I have tried [r,sigma] = subexpr(expr). I cancelled this command after more than 1 hour of calculation. In addition, subexpr, if I have understood it correctly, only looks for one sigma.
I hope someone here can help me.
I am working with Matla 2017b and the symbolic toolbox

Answers (2)

Nikhil Sonavane
Nikhil Sonavane on 19 Feb 2021
Currently, subexpr function gives only one sigma as you correctly mentioned. I have brought this issue to the concerned people and it might be considered in any future release.
  1 Comment
Philipp Rupp
Philipp Rupp on 22 Feb 2021
Thanks for the answer.
I have now got one sigma with this command. (It has calculated for several hours)
Which I find strange, because the display from the live script "only" takes a few minutes.

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Walter Roberson
Walter Roberson on 19 Feb 2021
Edited: Walter Roberson on 19 Feb 2021
Complete hack:
ML = getMathMLForSym(rxppcol); %undocumented internal function
and parse the returned MathML to decode the sigma expressions
  1 Comment
Philipp Rupp
Philipp Rupp on 22 Feb 2021
Thanks for the answer.
Unfortunately the equation is too long. (See screenshot)

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