Add simplify kwarg in solve_for

Author: YingboMa

src/solve.jl

@@ -82,18 +82,23 @@ Assumes `length(eqs) == length(vars)`
 
 Currently only works if all equations are linear.
 """
-function solve_for(eqs, vars)
+function solve_for(eqs, vars; simplify=true)
     A, b = A_b(eqs, vars)
     #TODO: we need to make sure that `solve_for(eqs, vars)` contains no `vars`
-    _solve(A, b)
+    _solve(A, b, simplify)
 end
 
-function _solve(A::AbstractMatrix, b::AbstractArray)
+function _solve(A::AbstractMatrix, b::AbstractArray, do_simplify)
     A = SymbolicUtils.simplify.(Num.(A), polynorm=true)
     b = SymbolicUtils.simplify.(Num.(b), polynorm=true)
-    value.(SymbolicUtils.simplify.(sym_lu(A) \ b))
+    sol = value.(sym_lu(A) \ b)
+    do_simplify ? SymbolicUtils.simplify.(sol, polynorm=true) : sol
+end
+
+function _solve(a, b, do_simplify)
+    sol = value(b/a)
+    do_simplify ? SymbolicUtils.simplify(sol, polynorm=true) : sol
 end
-_solve(a, b) = value(SymbolicUtils.simplify(b/a, polynorm=true))
 
 # ldiv below