add mixed zono/polyzono 'linear_combination'

Author: schillic

src/ConcreteOperations/linear_combination.jl

@@ -36,3 +36,7 @@ function linear_combination(P1::AbstractPolynomialZonotope,
     SSPZ2 = convert(SimpleSparsePolynomialZonotope, P2)
     return linear_combination(SSPZ1, SSPZ2)
 end
+
+@commutative function linear_combination(Z::AbstractZonotope, P::AbstractPolynomialZonotope)
+    return linear_combination(convert(SparsePolynomialZonotope, Z), P)
+end

test/Sets/SparsePolynomialZonotope.jl

@@ -153,6 +153,9 @@ for N in [Float64, Float32, Rational{Int}]
     # no reasonable tests available here
     @test PZ_ch isa SimpleSparsePolynomialZonotope{N}
     @test center(PZ_ch) == N[-1, 3//2]
+    # mixed linear_combination
+    PZ_lc = linear_combination(PZ1, ZeroSet{N}(2))
+    @test PZ_lc isa SimpleSparsePolynomialZonotope{N}
 end
 
 for N in [Float64]