refactor: use SurrogatesBase in SurrogatesAbstractGPs

lib/SurrogatesAbstractGPs/src/SurrogatesAbstractGPs.jl

@@ -1,11 +1,10 @@
 module SurrogatesAbstractGPs
 
-import Surrogates: add_point!, AbstractSurrogate, std_error_at_point, _check_dimension
-export AbstractGPSurrogate, var_at_point, logpdf_surrogate
+using SurrogatesBase, AbstractGPs
 
-using AbstractGPs
+export AbstractGPSurrogate, logpdf_surrogate, update!, finite_posterior
 
-mutable struct AbstractGPSurrogate{X, Y, GP, GP_P, S} <: AbstractSurrogate
+mutable struct AbstractGPSurrogate{X, Y, GP, GP_P, S} <: AbstractStochasticSurrogate
     x::X
     y::Y
     gp::GP
@@ -20,29 +19,24 @@ end
 
 # predictor
 function (g::AbstractGPSurrogate)(val)
-    # Check to make sure dimensions of input matches expected dimension of surrogate
-    _check_dimension(g, val)
-
     return only(mean(g.gp_posterior([val])))
 end
 
-# for add point
-# copies of x and y need to be made because we get
-#"Error: cannot resize array with shared data " if we push! directly to x and y
-function add_point!(g::AbstractGPSurrogate, new_x, new_y)
-    if new_x in g.x
-        println("Adding a sample that already exists, cannot build AbstracgGPSurrogate.")
-        return
+function SurrogatesBase.update!(g::AbstractGPSurrogate, new_x, new_y)
+    for x in new_x
+        in(x, g.x) &&
+            error("Adding a sample that already exists, cannot update AbstractGPSurrogate!")
     end
-    x_copy = copy(g.x)
-    push!(x_copy, new_x)
-    y_copy = copy(g.y)
-    push!(y_copy, new_y)
-    updated_posterior = posterior(g.gp(x_copy, g.Σy), y_copy)
-    g.x, g.y, g.gp_posterior = x_copy, y_copy, updated_posterior
+    g.x = vcat(g.x, new_x)
+    g.y = vcat(g.y, new_y)
+    g.gp_posterior = posterior(g.gp(g.x, g.Σy), g.y)
     nothing
 end
 
+function SurrogatesBase.finite_posterior(g::AbstractGPSurrogate, xs)
+    g.gp_posterior(xs)
+end
+
 function std_error_at_point(g::AbstractGPSurrogate, val)
     return sqrt(only(var(g.gp_posterior([val]))))
 end