Change typeof(x) <: y to x isa y

Author: Pepijn de Vos

src/MATLABDiffEq.jl

@@ -37,7 +37,7 @@ function DiffEqBase.__solve(
     f = prob.f
     u0 = prob.u0
 
-    if typeof(saveat) <: Number
+    if saveat isa Number
         tspan = Array(prob.tspan[1]:saveat:prob.tspan[2])
         tspan = sort(unique([prob.tspan[1]; tspan; prob.tspan[2]]))
     else