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

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

Answer 1

[Nikhil Sonavane]

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.

[Philipp Rupp]

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.

Answer 2

[Walter Roberson]

Complete hack:

ML = getMathMLForSym(rxppcol);   %undocumented internal function

and parse the returned MathML to decode the sigma expressions

[Philipp Rupp]

Thanks for the answer.

Unfortunately the equation is too long. (See screenshot)