core: adding time_func model

This model permits through a lambda function to applyt t -> f(t).

- adding tests for time_func model and adpting Izhikevitch simulation
- update public-api.cpp

lib/include/irritator/core.hpp

@@ -13,7 +13,8 @@
 #include <cmath>
 #include <cstdint>
 #include <cstring>
-//#include <iostream>
+
+
 namespace irt {
 
 using i8 = int8_t;
@@ -97,6 +98,9 @@ enum class status
     model_cross_empty_init_message,
     model_cross_bad_init_message,
     model_cross_bad_external_message,
+
+    model_time_func_empty_init_message,
+    model_time_func_bad_init_message,
 };
 
 constexpr bool
@@ -2472,7 +2476,8 @@ enum class dynamics_type : i8
     counter,
     generator,
     constant,
-    cross
+    cross,
+    time_func
 };
 
 struct model
@@ -2802,6 +2807,42 @@ struct constant
         return status::success;
     }
 };
+
+struct time_func
+{
+    model_id id;
+    output_port_id y[1];
+    time sigma;
+    double value;
+    double (*f)(double);
+    status initialize(data_array<message, message_id>& init_messages) noexcept
+    {
+        sigma = 1.0;
+        value = sigma;
+        return status::success;
+    }
+
+    status transition(data_array<input_port, input_port_id>& input_ports,
+        time t,
+        time /*e*/,
+        time /*r*/) noexcept
+    {
+
+        sigma = (*f)(t) ;
+        value = sigma;
+
+        return status::success;
+    }
+
+    status lambda(
+        data_array<output_port, output_port_id>& output_ports) noexcept
+    {
+        auto& port = output_ports.get(y[0]);
+        port.messages.emplace_front(value);
+
+        return status::success;
+    }
+};
 struct cross
 {
     model_id id;
@@ -2847,6 +2888,7 @@ struct cross
                     status::model_cross_bad_external_message);
 
                 value =  msg.to_real_64(0) ;
+                
                 have_message = true;
             }
         }
@@ -2862,6 +2904,7 @@ struct cross
                     status::model_cross_bad_external_message);
 
                 if_value = msg.to_real_64(0);
+                have_message = true;
             }
         }
         if (auto* port = input_ports.try_to_get(x[port_else_value]); port) {
@@ -2875,6 +2918,7 @@ struct cross
                     status::model_cross_bad_external_message);
 
                 else_value = msg.to_real_64(0);
+                have_message = true;
             }
         }
 
@@ -3557,6 +3601,7 @@ struct simulation
     data_array<generator, dynamics_id> generator_models;
     data_array<constant, dynamics_id> constant_models;
     data_array<cross, dynamics_id> cross_models;
+    data_array<time_func, dynamics_id> time_func_models;
 
     scheduller sched;
 
@@ -3596,6 +3641,7 @@ struct simulation
         irt_return_if_bad(generator_models.init(model_capacity));
         irt_return_if_bad(constant_models.init(model_capacity));
         irt_return_if_bad(cross_models.init(model_capacity));
+        irt_return_if_bad(time_func_models.init(model_capacity));
 
         return status::success;
     }
@@ -3645,8 +3691,10 @@ struct simulation
             mdl.type = dynamics_type::generator;
         else if constexpr (std::is_same_v<Dynamics, constant>)
             mdl.type = dynamics_type::constant;
-        else
+        else if constexpr (std::is_same_v<Dynamics, cross>)
             mdl.type = dynamics_type::cross;
+        else
+            mdl.type = dynamics_type::time_func;
 
         if constexpr (is_detected_v<initialize_function_t, Dynamics>) {
             //if constexpr (is_detected_v<has_init_port_t, Dynamics>) {
@@ -3833,6 +3881,8 @@ struct simulation
             return make_transition(mdl, constant_models.get(mdl.id), t, o);
         case dynamics_type::cross:
             return make_transition(mdl, cross_models.get(mdl.id), t, o);
+        case dynamics_type::time_func:
+            return make_transition(mdl, time_func_models.get(mdl.id), t, o);
         }
 
         return make_transition(mdl, none_models.get(mdl.id), t, o);

lib/test/public-api.cpp

@@ -87,7 +87,7 @@ dot_graph_save(const irt::simulation& sim, std::FILE* os)
         }
     }
 }
-
+double f (double t) {return t*t;}
 int
 main()
 {
@@ -734,6 +734,42 @@ main()
         expect(cnt.number == 9_ul);
     };
 
+    "time_func"_test = [] {
+        irt::simulation sim;
+
+        expect(irt::is_success(sim.init(16lu, 256lu)));
+        expect(sim.time_func_models.can_alloc(1));
+        expect(sim.counter_models.can_alloc(1));
+
+        auto& time_fun = sim.time_func_models.alloc();
+        auto& cnt = sim.counter_models.alloc();
+
+        double f(double t);
+        time_fun.f = &f;
+        expect(sim.models.can_alloc(2));
+        expect(irt::is_success(sim.alloc(time_fun, sim.time_func_models.get_id(time_fun))));
+        expect(irt::is_success(sim.alloc(cnt, sim.counter_models.get_id(cnt))));
+
+        expect(sim.connect(time_fun.y[0], cnt.x[0]) == irt::status::success);
+
+        expect(sim.begin == irt::time_domain<irt::time>::zero);
+        expect(sim.end == irt::time_domain<irt::time>::infinity);
+
+        sim.end = 30.0;
+
+        irt::time t = sim.begin;
+        irt::status st;
+
+        do {
+            st = sim.run(t);
+            expect(irt::is_success(st));
+            expect(time_fun.value == t*t);
+            expect(cnt.number <= static_cast<long unsigned>(t));
+        } while (t < sim.end);
+
+
+    };
+
     "lotka_volterra_simulation"_test = [] {
         irt::simulation sim;
 
@@ -865,18 +901,18 @@ main()
         irt::simulation sim;
         
         expect(irt::is_success(sim.init(64lu, 256lu)));
-        expect(sim.constant_models.can_alloc(4));
+        expect(sim.constant_models.can_alloc(2));
         expect(sim.adder_2_models.can_alloc(3));
         expect(sim.adder_4_models.can_alloc(1));
         expect(sim.mult_2_models.can_alloc(1));
         expect(sim.integrator_models.can_alloc(2));
         expect(sim.quantifier_models.can_alloc(2));
         expect(sim.cross_models.can_alloc(2));
+        expect(sim.time_func_models.can_alloc(1));
 
-        auto& c1 = sim.constant_models.alloc();
-        auto& c2 = sim.constant_models.alloc();
-        auto& c3 = sim.constant_models.alloc();
-        auto& c4 = sim.constant_models.alloc();
+        auto& time_fun = sim.time_func_models.alloc();
+        auto& constant = sim.constant_models.alloc();
+        auto& constant2 = sim.constant_models.alloc();
         auto& sum_a = sim.adder_2_models.alloc();
         auto& sum_b = sim.adder_2_models.alloc();
         auto& sum_c = sim.adder_4_models.alloc();
@@ -889,14 +925,13 @@ main()
         auto& cross = sim.cross_models.alloc();
         auto& cross2 = sim.cross_models.alloc();
 
-
         double a = 0.2; 
         double b = 2.0; 
         double c = -56.0; 
         double d = -16.0; 
         double I = -99.0; 
         double vt = 30.0;
-
+        double f(double);
 
        
         integrator_a.current_value = 0.0;
@@ -922,24 +957,26 @@ main()
         sum_b.input_coeffs[1] = a*b;
         sum_c.input_coeffs[0] = 0.04;
         sum_c.input_coeffs[1] = 5.0;
-        sum_c.input_coeffs[2] = 1.0;
+        sum_c.input_coeffs[2] = 140.0;
         sum_c.input_coeffs[3] = 1.0;
         sum_d.input_coeffs[0] = 1.0;
-        sum_d.input_coeffs[1] = 1.0;
-        c1.value = 140.0;
-        c2.value = I;
-        c3.value = c;
-        c4.value = d;
+        sum_d.input_coeffs[1] = d;
+
+        constant.value = 1.0;
+        constant2.value = c;
+
         cross.threshold = vt;
         cross2.threshold = vt;
 
+        time_fun.f = &f;
+     
         expect(sim.models.can_alloc(12));
         !expect(irt::is_success(
-               sim.alloc(c1, sim.constant_models.get_id(c1),"140")));
+               sim.alloc(time_fun, sim.time_func_models.get_id(time_fun),"tfun")));
         !expect(irt::is_success(
-               sim.alloc(c2, sim.constant_models.get_id(c2),"I")));
+               sim.alloc(constant, sim.constant_models.get_id(constant),"1.0")));
         !expect(irt::is_success(
-               sim.alloc(c3, sim.constant_models.get_id(c3),"c")));
+               sim.alloc(constant2, sim.constant_models.get_id(constant2),"-56.0")));
 
         !expect(irt::is_success(
           sim.alloc(sum_a, sim.adder_2_models.get_id(sum_a), "sum_a")));
@@ -969,7 +1006,7 @@ main()
 
         expect(sim.connect(integrator_a.y[0], cross.x[0]) ==
                irt::status::success);
-        expect(sim.connect(c3.y[0], cross.x[1]) ==
+        expect(sim.connect(constant2.y[0], cross.x[1]) ==
                irt::status::success);
         expect(sim.connect(integrator_a.y[0], cross.x[2]) ==
                irt::status::success);
@@ -987,9 +1024,9 @@ main()
         expect(sim.connect( cross.y[0], sum_b.x[1]) ==
                irt::status::success);
 
-        expect(sim.connect(c1.y[0] ,sum_c.x[2]) ==
+        expect(sim.connect(constant.y[0] ,sum_c.x[2]) ==
                irt::status::success);
-        expect(sim.connect(c2.y[0] ,sum_c.x[3]) ==
+        expect(sim.connect(time_fun.y[0] ,sum_c.x[3]) ==
                irt::status::success);
 
         expect(sim.connect(sum_c.y[0],sum_a.x[0]) ==