Hi everyone,
I've got a long symbolic expression I would like to simplify by substitution in a live script. Unfortunatelly, I'm not able to provide much information or a lot of code, since there is an NDA but I hope you can help anyways. Sorry for the inconvenience.
Implementation of some equations lead to a quite long expression - so, I've already done some simplifications via simplify(), combine(), subs(), factor() and collect().
My current formulation looks like this:
where 
Every variable included is defined as symbolic and dependent to additional symbolic variables (with exception of 
). Coming from this, I would like to substitute:
(similar for subscript v)I already tried different variations with the subs()-function (Annotation: ff4 is a previous form of ff6 (without two simplification steps)):
ff7=subs(ff6,6*(alpha_f^2 + 3*alpha_f + 2)/(6*alpha_f^2 + 7*alpha_f + 2),beta_l)
ff8=subs(ff7,(6*(alpha_v^2 + 3*alpha_v + 2)/(6*alpha_v^2 + 7*alpha_v + 2),beta_v)
eqn_6_f = beta_l == 6*(alpha_f^2 + 3*alpha_f + 2)/(6*alpha_f^2 + 7*alpha_f + 2)
subs(ff4,rhs(eqn_6_f),lhs(eqn_6_f))
subs(ff4,6*(alpha_f^2 + 3*alpha_f + 2)/(6*alpha_f^2 + 7*alpha_f + 2),lhs(eqn_6_f))
subs(ff4,6*(alpha_v^2 + 3*alpha_v + 2)/(6*alpha_v^2 + 7*alpha_v + 2),beta_v)
(also more variation which is not shown herr - like: string2sym(char(6*(alpha_f^2 + 3*alpha_f + 2)/(6*alpha_f^2 + 7*alpha_f + 2))) within the subs()-function)
Currently I'm really confused why the substitution is not working like intended and hopefully you can help me.
Your help is really appreciated greatly.
Thank you so much in advance.
Cheers,
Peter
PS: previosly, I used the subs()-function solely "the other way round" (e.g. subs(equation, symbolic variable x, expression for x)) which worked like intended.
with term1,
with term2,
with beta
