improve QobjEvo construction

Author: ytdHuang

src/qobj/quantum_object_evo.jl

@@ -180,8 +180,12 @@ function QuantumObjectEvolution(
     return QuantumObjectEvolution(data, type, dims)
 end
 
-QuantumObjectEvolution(op::QuantumObject, f::Function; type::Union{Nothing,QuantumObjectType} = nothing) =
-    QuantumObjectEvolution(((op, f),); type = type)
+# this is a extra method if user accidentally specify `QuantumObjectEvolution( (op, func) )` or `QuantumObjectEvolution( ((op, func)) )`
+QuantumObjectEvolution(op_func::Tuple{QuantumObject,Function}, α::Union{Nothing,Number} = nothing; type::Union{Nothing,QuantumObjectType} = nothing) =
+    QuantumObjectEvolution((op_func,), α; type = type)
+
+QuantumObjectEvolution(op::QuantumObject, f::Function, α::Union{Nothing,Number} = nothing; type::Union{Nothing,QuantumObjectType} = nothing) =
+    QuantumObjectEvolution(((op, f),), α; type = type)
 
 function QuantumObjectEvolution(
     op::QuantumObject,
@@ -229,13 +233,15 @@ Parse the `op_func_list` and generate the data for the `QuantumObjectEvolution`
     N = length(op_func_list_types)
 
     dims_expr = ()
+    func_methods_expr = ()
     first_op = nothing
     data_expr = :(0)
     qobj_expr_const = :(0)
 
     for i in 1:N
         op_func_type = op_func_list_types[i]
         if op_func_type <: Tuple
+            # check the structure of the tuple
             length(op_func_type.parameters) == 2 || throw(ArgumentError("The tuple must have two elements."))
             op_type = op_func_type.parameters[1]
             func_type = op_func_type.parameters[2]
@@ -248,6 +254,7 @@ Parse the `op_func_list` and generate the data for the `QuantumObjectEvolution`
             op = :(op_func_list[$i][1])
             data_type = op_type.parameters[1]
             dims_expr = (dims_expr..., :($op.dims))
+            func_methods_expr = (func_methods_expr..., :(methods(op_func_list[$i][2], [Any, Real]))) # [Any, Real] means each func must accept 2 arguments
             if i == 1
                 first_op = :($op)
             end
@@ -267,10 +274,16 @@ Parse the `op_func_list` and generate the data for the `QuantumObjectEvolution`
     end
 
     quote
+        # check the dims of the operators
         dims = tuple($(dims_expr...))
-
         allequal(dims) || throw(ArgumentError("The dimensions of the operators must be the same."))
 
+        # check if each func accepts 2 arguments
+        func_methods = tuple($(func_methods_expr...))
+        for f_method in func_methods
+            length(f_method.ms) == 0 && throw(ArgumentError("The following function must accept two arguments: `$(f_method.mt.name)(p, t)` with t<:Real"))
+        end
+
         data_expr_const = $qobj_expr_const isa Integer ? $qobj_expr_const : _make_SciMLOperator($qobj_expr_const, α)
 
         data_expr = data_expr_const + $data_expr

test/core-test/quantum_objects_evo.jl

@@ -182,6 +182,7 @@
         @test isconstant(H_td) == false
         @test isconstant(QobjEvo(a)) == true
         @test isoper(H_td) == true
+        @test QobjEvo(a, coef1) == QobjEvo((a, coef1))
 
         # SuperOperator
         X = a * a'
@@ -205,7 +206,9 @@
         @test isconstant(L_td) == false
         @test issuper(L_td) == true
 
+        coef_wrong(t) = exp(-t)
         @test_logs (:warn,) (:warn,) liouvillian(H_td * H_td) # warnings from lazy tensor
+        @test_throws ArgumentError QobjEvo(a, coef_wrong)
         @test_throws MethodError QobjEvo([[a, coef1], a' * a, [a', coef2]])
         @test_throws ArgumentError H_td(ρvec, p, t)
         @test_throws ArgumentError cache_operator(H_td, ρvec)