fix: use tspan in updated_u0_p for initial values dependent on time

Author: AayushSabharwal

src/remake.jl

@@ -118,7 +118,7 @@ function remake(prob::ODEProblem; f = missing,
         tspan = prob.tspan
     end
 
-    newu0, newp = updated_u0_p(prob, u0, p; interpret_symbolicmap, use_defaults)
+    newu0, newp = updated_u0_p(prob, u0, p, tspan[1]; interpret_symbolicmap, use_defaults)
 
     iip = isinplace(prob)
 
@@ -214,7 +214,7 @@ function remake(prob::BVProblem{uType, tType, iip, nlls}; f = missing, bc = miss
         tspan = prob.tspan
     end
 
-    u0, p = updated_u0_p(prob, u0, p; interpret_symbolicmap, use_defaults)
+    u0, p = updated_u0_p(prob, u0, p, tspan[1]; interpret_symbolicmap, use_defaults)
 
     if problem_type === missing
         problem_type = prob.problem_type
@@ -280,7 +280,7 @@ function remake(prob::SDEProblem;
         tspan = prob.tspan
     end
 
-    u0, p = updated_u0_p(prob, u0, p; interpret_symbolicmap, use_defaults)
+    u0, p = updated_u0_p(prob, u0, p, tspan[1]; interpret_symbolicmap, use_defaults)
 
     if noise === missing
         noise = prob.noise
@@ -496,35 +496,35 @@ anydict(d) = Dict{Any, Any}(d)
 anydict() = Dict{Any, Any}()
 
 function _updated_u0_p_internal(
-        prob, ::Missing, ::Missing; interpret_symbolicmap = true, use_defaults = false)
+        prob, ::Missing, ::Missing, t0; interpret_symbolicmap = true, use_defaults = false)
     return state_values(prob), parameter_values(prob)
 end
 function _updated_u0_p_internal(
-        prob, ::Missing, p; interpret_symbolicmap = true, use_defaults = false)
+        prob, ::Missing, p, t0; interpret_symbolicmap = true, use_defaults = false)
     u0 = state_values(prob)
 
     if p isa AbstractArray && isempty(p)
         return _updated_u0_p_internal(
-            prob, u0, parameter_values(prob); interpret_symbolicmap)
+            prob, u0, parameter_values(prob), t0; interpret_symbolicmap)
     end
     eltype(p) <: Pair && interpret_symbolicmap || return u0, p
     defs = default_values(prob)
     p = fill_p(prob, anydict(p); defs, use_defaults)
-    return _updated_u0_p_symmap(prob, u0, Val(false), p, Val(true))
+    return _updated_u0_p_symmap(prob, u0, Val(false), p, Val(true), t0)
 end
 
 function _updated_u0_p_internal(
-        prob, u0, ::Missing; interpret_symbolicmap = true, use_defaults = false)
+        prob, u0, ::Missing, t0; interpret_symbolicmap = true, use_defaults = false)
     p = parameter_values(prob)
 
     eltype(u0) <: Pair || return u0, p
     defs = default_values(prob)
     u0 = fill_u0(prob, anydict(u0); defs, use_defaults)
-    return _updated_u0_p_symmap(prob, u0, Val(true), p, Val(false))
+    return _updated_u0_p_symmap(prob, u0, Val(true), p, Val(false), t0)
 end
 
 function _updated_u0_p_internal(
-        prob, u0, p; interpret_symbolicmap = true, use_defaults = false)
+        prob, u0, p, t0; interpret_symbolicmap = true, use_defaults = false)
     isu0symbolic = eltype(u0) <: Pair
     ispsymbolic = eltype(p) <: Pair && interpret_symbolicmap
 
@@ -538,7 +538,7 @@ function _updated_u0_p_internal(
     if ispsymbolic
         p = fill_p(prob, anydict(p); defs, use_defaults)
     end
-    return _updated_u0_p_symmap(prob, u0, Val(isu0symbolic), p, Val(ispsymbolic))
+    return _updated_u0_p_symmap(prob, u0, Val(isu0symbolic), p, Val(ispsymbolic), t0)
 end
 
 function fill_u0(prob, u0; defs = nothing, use_defaults = false)
@@ -629,7 +629,7 @@ function fill_p(prob, p; defs = nothing, use_defaults = false)
     return newvals
 end
 
-function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{false})
+function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{false}, t0)
     isdep = any(symbolic_type(v) !== NotSymbolic() for (_, v) in u0)
     isdep || return remake_buffer(prob, state_values(prob), keys(u0), values(u0)), p
 
@@ -642,13 +642,13 @@ function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{false})
     # FIXME: need to provide `u` since the observed function expects it.
     # This is sort of an implicit dependency on MTK. The values of `u` won't actually be
     # used, since any state symbols in the expression were substituted out earlier.
-    temp_state = ProblemState(; u = state_values(prob), p = p)
+    temp_state = ProblemState(; u = state_values(prob), p = p, t = t0)
     u0 = anydict(k => symbolic_type(v) === NotSymbolic() ? v : getu(prob, v)(temp_state)
     for (k, v) in u0)
     return remake_buffer(prob, state_values(prob), keys(u0), values(u0)), p
 end
 
-function _updated_u0_p_symmap(prob, u0, ::Val{false}, p, ::Val{true})
+function _updated_u0_p_symmap(prob, u0, ::Val{false}, p, ::Val{true}, t0)
     isdep = any(symbolic_type(v) !== NotSymbolic() for (_, v) in p)
     isdep || return u0, remake_buffer(prob, parameter_values(prob), keys(p), values(p))
 
@@ -661,13 +661,13 @@ function _updated_u0_p_symmap(prob, u0, ::Val{false}, p, ::Val{true})
     # FIXME: need to provide `p` since the observed function expects an `MTKParameters`
     # this is sort of an implicit dependency on MTK. The values of `p` won't actually be
     # used, since any parameter symbols in the expression were substituted out earlier.
-    temp_state = ProblemState(; u = u0, p = parameter_values(prob))
+    temp_state = ProblemState(; u = u0, p = parameter_values(prob), t = t0)
     p = anydict(k => symbolic_type(v) === NotSymbolic() ? v : getu(prob, v)(temp_state)
     for (k, v) in p)
     return u0, remake_buffer(prob, parameter_values(prob), keys(p), values(p))
 end
 
-function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{true})
+function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{true}, t0)
     isu0dep = any(symbolic_type(v) !== NotSymbolic() for (_, v) in u0)
     ispdep = any(symbolic_type(v) !== NotSymbolic() for (_, v) in p)
 
@@ -677,11 +677,11 @@ function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{true})
     end
     if !isu0dep
         u0 = remake_buffer(prob, state_values(prob), keys(u0), values(u0))
-        return _updated_u0_p_symmap(prob, u0, Val(false), p, Val(true))
+        return _updated_u0_p_symmap(prob, u0, Val(false), p, Val(true), t0)
     end
     if !ispdep
         p = remake_buffer(prob, parameter_values(prob), keys(p), values(p))
-        return _updated_u0_p_symmap(prob, u0, Val(true), p, Val(false))
+        return _updated_u0_p_symmap(prob, u0, Val(true), p, Val(false), t0)
     end
 
     varmap = merge(u0, p)
@@ -693,7 +693,7 @@ function _updated_u0_p_symmap(prob, u0, ::Val{true}, p, ::Val{true})
     remake_buffer(prob, parameter_values(prob), keys(p), values(p))
 end
 
-function updated_u0_p(prob, u0, p; interpret_symbolicmap = true, use_defaults = false)
+function updated_u0_p(prob, u0, p, t0 = nothing; interpret_symbolicmap = true, use_defaults = false)
     if u0 === missing && p === missing
         return state_values(prob), parameter_values(prob)
     end
@@ -712,7 +712,7 @@ function updated_u0_p(prob, u0, p; interpret_symbolicmap = true, use_defaults =
         return (u0 === missing ? state_values(prob) : u0),
         (p === missing ? parameter_values(prob) : p)
     end
-    return _updated_u0_p_internal(prob, u0, p; interpret_symbolicmap, use_defaults)
+    return _updated_u0_p_internal(prob, u0, p, t0; interpret_symbolicmap, use_defaults)
 end
 
 # overloaded in MTK to intercept symbolic remake