collecting "like terms" in an equation using symbolic toolbox

if I have a equation of such

syms gamma vg gn Va N0 deltN Ntr eps S0 deltS taop beta B k Sinj phi0 deltPhi phi_inj

equation =((gamma*vg*gn/Va)*((N0+deltN)-Ntr)/(1+eps*(S0+deltS))-1/taop)*(S0+deltS) + beta*B/Va*(N0+deltN)^2 + 2*k*sqrt(Sinj*(S0+deltS))*cos((phi0+deltPhi)-phi_inj);

How am I able to transform this equation using the symbolic toolbox, such that my final result will be in terms of deltS, deltN and deltPhi.

I have already used

equation=collect(equation, deltS); equation=collect(equation, deltN); equation=collect(equation, deltPhi);

but I still get factors such as deltX(deltY, deltZ). but I only want a linear equation such

deltX wont be a function of either deltY or deltZ,

Thanks

Answer 1

[Arsalan]

My apologizes for using the term linear equation (it should of been used there). I just want the symbolic toolbox to give me factors of such:

deltN*()+deltS()+deltPhi()

where with the factors of deltN I do not want any terms of deltS or deltPhi with the factors of deltS I do not want any terms of deltN or deltPhi with the factors of deltPhi I do not want any terms of deltS or deltN

Thanks, Arsalan

[Walter Roberson]

That isn't possible. Your first term has deltN in the numerator and deltS in the denominator. Those terms are not separable.

Answer 2

[Walter Roberson]

It is not possible to extract a linear equation in those variables. For example the term beta*B/Va*(N0+deltN)^2 includes deltN^2 which is non-linear.

I do not understand your reference to deltX, deltY, deltZ? Those do not appear in your equation.