Using the output of deSolve
compute the dynamical terms for the output of root_solve
     
    
    compute_terms_steady(varslist, y_eq, pars, s, i)
 
     
    
    Arguments
    - varslist
 
a list with variable names attached
 
- y_eq
 
a matrix, the output of rootSolve
 
- pars
 
a list
 
- s
 
the vector species index
 
- i
 
the host species index