Define variables through new @defvar macro

src/parts/epi_readouts.jl

@@ -2,7 +2,7 @@ module EPIReadouts
 import ...Containers: BaseSequence, get_index_single_TR
 import ..Trapezoids: Trapezoid, opposite_kspace_lines, LineReadout
 import ...Components: ADC
-import ...Variables: get_free_variable, VariableType, qval, qval3, set_simple_constraints!, resolution, inverse_voxel_size, inverse_fov, resolution, get_readout, apply_simple_constraint!, effective_time, voxel_size, ramp_overlap, oversample, dwell_time
+import ...Variables: get_free_variable, VariableType, set_simple_constraints!, get_readout, apply_simple_constraint!, variables, @defvar
 import ...Pathways: PathwayWalker, update_walker_till_time!, walk_pathway!
 
 """
@@ -11,16 +11,16 @@ import ...Pathways: PathwayWalker, update_walker_till_time!, walk_pathway!
 Defines an (accelerated) EPI readout.
 
 ## Parameters
-- [`resolution`](@ref): Resolution of the final image in the frequency- and phase-encode directions.
+- [`variables.resolution`](@ref): Resolution of the final image in the frequency- and phase-encode directions.
 - `recenter`: if true, the signal will be recentred in k-space after the EPI readout.
 - `group`: name of the group used to rotate the readout gradients (default: :FOV).
 
 ## Variables:
-- [`voxel_size`](@ref): size of the voxel in the frequency- and phase-encode directions.
-- [`fov`](@ref): size of the FOV in the frequency- and phase-encode directions.
-- [`ramp_overlap`](@ref): what fraction of the gradient ramp should overlap with the readout.
-- [`oversample`](@ref): by how much to oversample in the frequency-encode direcion.
-- [`dwell_time`](@ref): dwell time in the frequency-encode direction
+- [`variables.voxel_size`](@ref): size of the voxel in the frequency- and phase-encode directions.
+- [`variables.fov`](@ref): size of the FOV in the frequency- and phase-encode directions.
+- [`variables.ramp_overlap`](@ref): what fraction of the gradient ramp should overlap with the readout.
+- [`variables.oversample`](@ref): by how much to oversample in the frequency-encode direcion.
+- [`variables.dwell_time`](@ref): dwell time in the frequency-encode direction
 """
 struct EPIReadout{N} <: BaseSequence{N}
     start_gradient :: Trapezoid
@@ -32,7 +32,7 @@ struct EPIReadout{N} <: BaseSequence{N}
     ky_lines :: AbstractVector{<:Integer}
 end
 
-function EPIReadout(; resolution::AbstractVector{<:Integer}, recenter=false, group=:FOV, ky_lines=nothing, variables...)
+function EPIReadout(; resolution::AbstractVector{<:Integer}, recenter=false, group=:FOV, ky_lines=nothing, vars...)
     if length(resolution) != 2
         error("EPIReadout expects the image resolution in the x- and y-direction.")
     end
@@ -49,28 +49,30 @@ function EPIReadout(; resolution::AbstractVector{<:Integer}, recenter=false, gro
         get_free_variable(nothing),
         ky_lines
     )
-    apply_simple_constraint!(qval3(res.start_gradient), VariableType[-qval(pos)/2, ky_lines[1] * res.ky_step, 0.])
+    apply_simple_constraint!(variables.qvec(res.start_gradient), VariableType[-variables.qvec(pos)[1]/2, ky_lines[1] * res.ky_step, 0.])
     if recenter
         sign = isodd(length(ky_lines)) ? -1 : 1
-        apply_simple_constraint!(qval3(res.recenter_gradient), VariableType[sign * qval(pos)/2, -ky_lines[end] * res.ky_step, 0.])
+        apply_simple_constraint!(variables.qvec(res.recenter_gradient), VariableType[sign * variables.qvec(pos)[1]/2, -ky_lines[end] * res.ky_step, 0.])
     end
     for shift in unique(ky_lines[2:end] - ky_lines[1:end-1])
-        res.blips[shift] = Trapezoid(orientation=[0, shift > 0 ? 1 : -1, 0], group=group, qval=abs(shift) * res.ky_step)
+        res.blips[shift] = Trapezoid(qvec=[0., shift * res.ky_step, 0.], group=group)
     end
-    set_simple_constraints!(res, variables)
+    set_simple_constraints!(res, vars)
     return res
 end
 
-inverse_fov(epi::EPIReadout) = [inverse_fov(epi.positive_line), 1e3 * epi.ky_step]
-inverse_voxel_size(epi::EPIReadout) = [inverse_voxel_size(epi.positive_line), 1e3 * epi.ky_step * maximum(abs.(epi.ky_lines))]
-resolution(epi::EPIReadout) = [resolution(epi.positive_line), maximum(abs.(epi.ky_lines))]
+@defvar readout begin
+    inverse_fov(epi::EPIReadout) = [variables.inverse_fov(epi.positive_line), 1e3 * epi.ky_step]
+    inverse_voxel_size(epi::EPIReadout) = [variables.inverse_voxel_size(epi.positive_line)[1], 1e3 * epi.ky_step * maximum(abs.(epi.ky_lines))]
+    resolution(epi::EPIReadout) = [variables.resolution(epi.positive_line), maximum(abs.(epi.ky_lines))]
+end
 get_readout(epi::EPIReadout) = epi.positive_line
-function effective_time(epi::EPIReadout)
+@defvar function effective_time(epi::EPIReadout)
     index = findfirst(iszero, epi.ky_lines)
     if isnothing(index)
         error("EPI readout does not pass through the centre of k-space")
     end
-    return effective_time(epi, index * 2)
+    return variables.effective_time(epi, index * 2)
 end
 
 function get_index_single_TR(epi::EPIReadout, index::Integer)
@@ -101,7 +103,7 @@ function walk_pathway!(epi::EPIReadout, walker::PathwayWalker, pulse_effects::Ve
     if nreadout[] > 0
         return false
     end
-    update_walker_till_time!(walker, block_start_time + effective_time(epi))
+    update_walker_till_time!(walker, block_start_time + variables.effective_time(epi))
     return true
 end