Fix GenericPulse frequency calculation

src/components/pulses/generic_pulses.jl

@@ -102,16 +102,16 @@ end
 function frequency(gp::GenericPulse, time::Number)
     i2 = findfirst(t -> t > time, gp.time)
     if isnothing(i2)
-        @assert time ≈ fp.time[end]
-        i2 = length(time)
+        @assert time ≈ gp.time[end]
+        i2 = length(gp.time)
     end
-    if i2 != length(time) && time ≈ fp.time[i2 + 1]
-        i2 += 1
+    if !isone(i2) && time ≈ gp.time[i2 - 1]
+        i2 -= 1
     end
-    if time ≈ fp.time[i2]
+    if time ≈ gp.time[i2]
         if i2 == 1
             return (gp.phase[2] - gp.phase[1]) / (gp.time[2] - gp.time[1]) / 360
-        elseif i2 == length(time)
+        elseif i2 == length(gp.time)
             return (gp.phase[end] - gp.phase[end-1]) / (gp.time[end] - gp.time[end-1]) / 360
         end
         return (gp.phase[i2 + 1] - gp.phase[i2 - 1]) / (gp.time[i2 + 1] - gp.time[i2 - 1]) / 360

test/runtests.jl

@@ -2,6 +2,7 @@ using MRIBuilder
 using Test
 
 @testset "MRIBuilder.jl" begin
+    include("test_components.jl")
     include("test_sequences.jl")
     include("test_IO.jl")
     include("test_plot.jl")

test/test_components.jl

+@testset "test_components.jl" begin
+    @testset "probing GenericPulse" begin
+        gp = GenericPulse([0., 1., 3., 4.], [1., 2., 3., 0.], [0., 90., 180., 180.])
+        @test amplitude(gp, 0.) ≈ 1.
+        @test amplitude(gp, 1.) ≈ 2.
+        @test amplitude(gp, 0.25) ≈ 1.25
+        @test amplitude(gp, 2.5) ≈ 2.75
+        @test amplitude(gp, 3.5) ≈ 1.5
+        @test amplitude(gp, 4.) ≈ 0.
+
+        @test phase(gp, 0.) ≈ 0.
+        @test phase(gp, 1.) ≈ 90.
+        @test phase(gp, 0.25) ≈ 90/4
+        @test phase(gp, 2.5) ≈ 90 * 7/4
+        @test phase(gp, 3.5) ≈ 180.
+        @test phase(gp, 4.) ≈ 180.
+
+        @test frequency(gp, 0.) ≈ 1/4
+        @test frequency(gp, 1.) ≈ 1/6
+        @test frequency(gp, 0.25) ≈ 1/4
+        @test frequency(gp, 2.5) ≈ 1/8
+        @test frequency(gp, 3.) ≈ 1/12
+        @test frequency(gp, 3.5) ≈ 0.
+        @test frequency(gp, 4.) ≈ 0.
+    end
+
+end

test/test_sequences.jl

@@ -113,14 +113,16 @@
                 @test 1. - t_pulse ≈ min_rise_time rtol=1e-4
                 @test flip_angle(pulse) ≈ 90.
                 @test iszero(phase(pulse))
+                @test iszero(phase(seq, 1.))
+                @test iszero(frequency(seq, 1.))
+
                 @test isnothing(get_pulse(seq, 10.))
+                @test isnan(phase(seq, 10.))
+                @test isnan(frequency(seq, 10.))
+    
                 gp = GenericPulse(pulse, 0., 1.)
                 @test gp.amplitude[1] ≈ 0. atol=1e-8
                 @test gp.amplitude[end] ≈ amplitude(pulse, 1.) rtol=1e-2
-                @test iszero(phase(pulse, 1.)) rtol=1e-2
-                @test iszero(frequency(pulse, 1.)) rtol=1e-2
-                @test isnan(phase(pulse, 1.)) rtol=1e-2
-                @test isnan(frequency(pulse, 1.)) rtol=1e-2
                 @test all(iszero.(gp.phase))
 
                 (pulse, t_pulse) = get_pulse(seq, 35.)