Optimize ArbitraryMotion (continuation)

KomaMRIBase/src/KomaMRIBase.jl

@@ -31,6 +31,7 @@ include("datatypes/Phantom.jl")
 include("datatypes/simulation/DiscreteSequence.jl")
 include("timing/TimeStepCalculation.jl")
 include("timing/TrapezoidalIntegration.jl")
+include("timing/UnitTime.jl")
 
 # Main
 export γ    # gyro-magnetic ratio [Hz/T]
@@ -51,8 +52,7 @@ export NoMotion, SimpleMotion, ArbitraryMotion
 export SimpleMotionType
 export Translation, Rotation, HeartBeat
 export PeriodicTranslation, PeriodicRotation, PeriodicHeartBeat
-export get_spin_coords, sort_motions!
-export LinearInterpolator
+export get_spin_coords
 # Secondary
 export get_kspace, rotx, roty, rotz
 # Additionals

KomaMRIBase/src/datatypes/Phantom.jl

@@ -69,10 +69,7 @@ Base.getindex(x::Phantom, i::Integer) = x[i:i]
 """Compare two phantoms"""
 Base.:(==)(obj1::Phantom, obj2::Phantom) = reduce(
     &,
-    [
-        getfield(obj1, field) == getfield(obj2, field) for
-        field in Iterators.filter(x -> !(x == :name), fieldnames(Phantom))
-    ],
+    [getfield(obj1, field) == getfield(obj2, field) for field in Iterators.filter(x -> !(x == :name), fieldnames(Phantom))],
 )
 Base.:(≈)(obj1::Phantom, obj2::Phantom)      = reduce(&, [getfield(obj1, field) ≈ getfield(obj2, field) for field in Iterators.filter(x -> !(x == :name), fieldnames(Phantom))])
 Base.:(==)(m1::MotionModel, m2::MotionModel) = false
@@ -88,7 +85,13 @@ Base.getindex(obj::Phantom, p::Union{AbstractRange,AbstractVector,Colon}) = begi
 end
 
 """Separate object spins in a sub-group (lightweigth)."""
-Base.view(obj::Phantom, p::Union{AbstractRange,AbstractVector,Colon}) = @views obj[p]
+Base.view(obj::Phantom, p::Union{AbstractRange,AbstractVector,Colon}) = begin
+    fields = []
+    for field in Iterators.filter(x -> !(x == :name), fieldnames(Phantom))
+        push!(fields, (field, @view(getfield(obj, field)[p])))
+    end
+    return Phantom(; name=obj.name, fields...)
+end
 
 """Addition of phantoms"""
 +(obj1::Phantom, obj2::Phantom) = begin
@@ -117,10 +120,6 @@ function get_dims(obj::Phantom)
     return dims
 end
 
-function sort_motions!(motion::MotionModel) 
-    return nothing
-end
-
 """
     obj = heart_phantom(...)
 
@@ -178,7 +177,7 @@ function heart_phantom(
         Dλ1=Dλ1[ρ .!= 0],
         Dλ2=Dλ2[ρ .!= 0],
         Dθ=Dθ[ρ .!= 0],
-        motion=SimpleMotion([
+        motion=SimpleMotion(
             PeriodicHeartBeat(;
                 period=period,
                 asymmetry=asymmetry,
@@ -189,7 +188,7 @@ function heart_phantom(
             PeriodicRotation(;
                 period=period, asymmetry=asymmetry, yaw=rotation_angle, pitch=0.0, roll=0.0
             ),
-        ]),
+        ),
     )
     return phantom
 end

KomaMRIBase/src/datatypes/phantom/motion/ArbitraryMotion.jl

@@ -2,13 +2,24 @@
 #       Interpolator{T,Degree,ETPType}, 
 #           Degree = Linear,Cubic.... 
 #           ETPType = Periodic, Flat...
-const LinearInterpolator = Interpolations.Extrapolation{
-    T,
-    1,
-    Interpolations.GriddedInterpolation{T,1,V,Gridded{Linear{Throw{OnGrid}}},Tuple{V}},
-    Gridded{Linear{Throw{OnGrid}}},
-    Periodic{Nothing},
-} where {T<:Real,V<:AbstractVector{T}}
+
+const Interpolator1D = Interpolations.GriddedInterpolation{
+    T,1,V,Itp,K
+} where {
+    T<:Real,
+    V<:AbstractArray{T},
+    Itp<:Interpolations.Gridded{Linear{Throw{OnGrid}}},
+    K<:Tuple{AbstractVector{T}},
+}
+
+const Interpolator2D = Interpolations.GriddedInterpolation{
+    T,2,V,Itp,K
+} where {
+    T<:Real,
+    V<:AbstractArray{T},
+    Itp<:Interpolations.Gridded{Linear{Throw{OnGrid}}},
+    K<:Tuple{AbstractVector{T}, AbstractVector{T}},
+}
 
 """
     motion = ArbitraryMotion(period_durations, dx, dy, dz)
@@ -43,106 +54,82 @@
         )
 ```
 """
-struct ArbitraryMotion{T<:Real,V<:AbstractVector{T}} <: MotionModel{T}
-    period_durations::Vector{T}
-    dx::Array{T,2}
-    dy::Array{T,2}
-    dz::Array{T,2}
-    ux::Vector{LinearInterpolator{T,V}}
-    uy::Vector{LinearInterpolator{T,V}}
-    uz::Vector{LinearInterpolator{T,V}}
-end
-
-function ArbitraryMotion(
-    period_durations::AbstractVector{T},
-    dx::AbstractArray{T,2},
-    dy::AbstractArray{T,2},
-    dz::AbstractArray{T,2},
-) where {T<:Real}
-    @warn "Note that ArbitraryMotion is under development so it is not optimized so far" maxlog = 1
-    Ns = size(dx)[1]
-    num_pieces = size(dx)[2] + 1
-    limits = times(period_durations, num_pieces)
-
-    #! format: off
-    Δ = zeros(Ns,length(limits),4)
-    Δ[:,:,1] = hcat(repeat(hcat(zeros(Ns,1),dx),1,length(period_durations)),zeros(Ns,1))
-    Δ[:,:,2] = hcat(repeat(hcat(zeros(Ns,1),dy),1,length(period_durations)),zeros(Ns,1))
-    Δ[:,:,3] = hcat(repeat(hcat(zeros(Ns,1),dz),1,length(period_durations)),zeros(Ns,1))
-
-    etpx = [extrapolate(interpolate((limits,), Δ[i,:,1], Gridded(Linear())), Periodic()) for i in 1:Ns]
-    etpy = [extrapolate(interpolate((limits,), Δ[i,:,2], Gridded(Linear())), Periodic()) for i in 1:Ns]
-    etpz = [extrapolate(interpolate((limits,), Δ[i,:,3], Gridded(Linear())), Periodic()) for i in 1:Ns]
-    #! format: on
-
-    return ArbitraryMotion(period_durations, dx, dy, dz, etpx, etpy, etpz)
+struct ArbitraryMotion{T} <: MotionModel{T}
+    t_start::T
+    t_end::T
+    dx::AbstractArray{T}
+    dy::AbstractArray{T}
+    dz::AbstractArray{T}
 end
 
 function Base.getindex(
     motion::ArbitraryMotion, p::Union{AbstractRange,AbstractVector,Colon}
 )
-    fields = []
-    for field in fieldnames(ArbitraryMotion)
-        if field in (:dx, :dy, :dz)
-            push!(fields, getfield(motion, field)[p, :])
-        elseif field in (:ux, :uy, :uz)
-            push!(fields, getfield(motion, field)[p])
-        else
-            push!(fields, getfield(motion, field))
-        end
-    end
-    return ArbitraryMotion(fields...)
+    return ArbitraryMotion(motion.t_start, motion.t_end, motion.dx[p,:], motion.dy[p,:], motion.dz[p,:])
+end
+function Base.view(
+    motion::ArbitraryMotion, p::Union{AbstractRange,AbstractVector,Colon}
+)
+    return ArbitraryMotion(motion.t_start, motion.t_end, @view(motion.dx[p,:]), @view(motion.dy[p,:]), @view(motion.dz[p,:]))
 end
 
 Base.:(==)(m1::ArbitraryMotion, m2::ArbitraryMotion) = reduce(&, [getfield(m1, field) == getfield(m2, field) for field in fieldnames(ArbitraryMotion)])
 Base.:(≈)(m1::ArbitraryMotion, m2::ArbitraryMotion)  = reduce(&, [getfield(m1, field) ≈ getfield(m2, field) for field in fieldnames(ArbitraryMotion)])
 
 function Base.vcat(m1::ArbitraryMotion, m2::ArbitraryMotion)
-    fields = []
-    @assert m1.period_durations == m2.period_durations "period_durations of both ArbitraryMotions must be the same"
-    for field in
-        Iterators.filter(x -> !(x == :period_durations), fieldnames(ArbitraryMotion))
-        push!(fields, [getfield(m1, field); getfield(m2, field)])
-    end
-    return ArbitraryMotion(m1.period_durations, fields...)
+    @assert (m1.t_start == m2.t_start) && (m1.t_end == m2.t_end) "Starting and ending times must be the same"
+    return ArbitraryMotion(m1.t_start, m1.t_end, [m1.dx; m2.dx], [m1.dy; m2.dy], [m1.dz; m2.dz])
 end
 
 """
     limits = times(obj.motion)
 """
 function times(motion::ArbitraryMotion)
-    period_durations = motion.period_durations
-    num_pieces = size(motion.dx)[2] + 1
-    return times(period_durations, num_pieces)
+    return range(motion.t_start, motion.t_end, length=size(motion.dx, 2))
+end
+
+function GriddedInterpolation(nodes, A, ITP)
+    return Interpolations.GriddedInterpolation{eltype(A), length(nodes), typeof(A), typeof(ITP), typeof(nodes)}(nodes, A, ITP)
+end
+
+function interpolate(motion::ArbitraryMotion{T}, Ns::Val{1}) where {T<:Real}
+    _, Nt = size(motion.dx)
+    t = similar(motion.dx, Nt); copyto!(t, collect(range(zero(T), oneunit(T), Nt)))
+    itpx = GriddedInterpolation((t, ), motion.dx[:], Gridded(Linear()))
+    itpy = GriddedInterpolation((t, ), motion.dy[:], Gridded(Linear()))
+    itpz = GriddedInterpolation((t, ), motion.dz[:], Gridded(Linear()))
+    return itpx, itpy, itpz
+end
+
+function interpolate(motion::ArbitraryMotion{T}, Ns::Val) where {T<:Real}
+    Ns, Nt = size(motion.dx)
+    id = similar(motion.dx, Ns); copyto!(id, collect(range(oneunit(T), T(Ns), Ns)))
+    t = similar(motion.dx, Nt);  copyto!(t, collect(range(zero(T), oneunit(T), Nt)))
+    itpx = GriddedInterpolation((id, t), motion.dx, Gridded(Linear()))
+    itpy = GriddedInterpolation((id, t), motion.dy, Gridded(Linear()))
+    itpz = GriddedInterpolation((id, t), motion.dz, Gridded(Linear()))
+    return itpx, itpy, itpz
+end
+
+function resample(itpx::Interpolator1D{T}, itpy::Interpolator1D{T}, itpz::Interpolator1D{T}, t::AbstractArray{T}) where {T<:Real}
+    return itpx.(t), itpy.(t), itpz.(t)
 end
 
-function times(period_durations::AbstractVector, num_pieces::Int)
-    # Pre-allocating memory
-    limits = zeros(eltype(period_durations), num_pieces * length(period_durations) + 1)
-
-    idx = 1
-    for i in 1:length(period_durations)
-        segment_increment = period_durations[i] / num_pieces
-        cumulative_sum = limits[idx]  # Start from the last computed value in limits
-        for j in 1:num_pieces
-            cumulative_sum += segment_increment
-            limits[idx + 1] = cumulative_sum
-            idx += 1
-        end
-    end
-    return limits
+function resample(itpx::Interpolator2D{T}, itpy::Interpolator2D{T}, itpz::Interpolator2D{T}, t::AbstractArray{T}) where {T<:Real}
+    Ns = size(itpx.coefs, 1)
+    id = similar(itpx.coefs, Ns)
+    copyto!(id, collect(range(oneunit(T), T(Ns), Ns)))
+    return itpx.(id, t), itpy.(id, t), itpz.(id, t)
 end
 
-# TODO: Calculate interpolation functions "on the fly"
 function get_spin_coords(
     motion::ArbitraryMotion{T},
     x::AbstractVector{T},
     y::AbstractVector{T},
     z::AbstractVector{T},
-    t::AbstractArray{T},
+    t::AbstractArray{T}
 ) where {T<:Real}
-    xt = x .+ reduce(vcat, [etp.(t) for etp in motion.ux])
-    yt = y .+ reduce(vcat, [etp.(t) for etp in motion.uy])
-    zt = z .+ reduce(vcat, [etp.(t) for etp in motion.uz])
-    return xt, yt, zt
-end
+    motion_functions = interpolate(motion, Val(size(x,1)))
+    ux, uy, uz = resample(motion_functions..., unit_time(t, motion.t_start, motion.t_end))
+    return x .+ ux, y .+ uy, z .+ uz
+end

KomaMRIBase/src/datatypes/phantom/motion/NoMotion.jl

@@ -7,6 +7,7 @@ x = x
 struct NoMotion{T<:Real} <: MotionModel{T} end
 
 Base.getindex(motion::NoMotion, p::Union{AbstractRange,AbstractVector,Colon}) = motion
+Base.view(motion::NoMotion, p::Union{AbstractRange,AbstractVector,Colon}) = motion
 
 Base.:(==)(m1::NoMotion, m2::NoMotion) = true
 Base.:(≈)(m1::NoMotion, m2::NoMotion)  = true
@@ -18,7 +19,7 @@ function get_spin_coords(
     x::AbstractVector{T},
     y::AbstractVector{T},
     z::AbstractVector{T},
-    t::AbstractArray{T},
+    t::AbstractArray{T}
 ) where {T<:Real}
     return x, y, z
 end