Support missing.

src/Waveforms.jl

@@ -15,6 +15,8 @@ Compute ``2\pi``-periodic square wave of `x` with a peak amplitude ``1``.
 """
 squarewave(x::Real) = ifelse(mod2pi(x) < π, 1.0, -1.0)
 
+squarewave(::Missing) = missing
+
 @doc raw"""
     squarewave(x, θ)
 
@@ -26,13 +28,19 @@ function squarewave(x::Real, θ::Real)
     ifelse(mod2pi(x) < 2π * θ, 1.0, -1.0)
 end
 
+squarewave(::Missing, ::Real) = missing
+squarewave(::Real, ::Missing) = missing
+squarewave(::Missing, ::Missing) = missing
+
 @doc raw"""
     squarewave1(x)
 
 Compute ``1``-periodic square wave of `x` with a peak amplitude ``1``.
 """
 squarewave1(x::Real) = ifelse(mod(x, 1) < 1/2, 1.0, -1.0)
 
+squarewave1(::Missing) = missing
+
 @doc raw"""
     squarewave1(x, θ)
 
@@ -44,6 +52,10 @@ function squarewave1(x::Real, θ::Real)
     ifelse(mod(x, 1) < θ, 1.0, -1.0)
 end
 
+squarewave1(::Missing, ::Real) = missing
+squarewave1(::Real, ::Missing) = missing
+squarewave1(::Missing, ::Missing) = missing
+
 @doc raw"""
     trianglewave(x)
 
@@ -54,6 +66,8 @@ function trianglewave(x::Real)
     ifelse(modx < π, 2modx/π - 1, -2modx/π + 3)
 end
 
+trianglewave(::Missing) = missing
+
 @doc raw"""
     trianglewave1(x)
 
@@ -64,18 +78,24 @@ function trianglewave1(x::Real)
     ifelse(modx < 1/2, 4modx - 1, -4modx + 3)
 end
 
+trianglewave1(::Missing) = missing
+
 @doc raw"""
     sawtoothwave(x)
 
 Compute ``2\pi``-periodic sawtooth wave of `x` with a peak amplitude ``1``.
 """
 sawtoothwave(x::Real) = rem2pi(x, RoundNearest) / π
 
+sawtoothwave(::Missing) = missing
+
 @doc raw"""
     sawtoothwave1(x)
 
 Compute ``1``-periodic sawtooth wave of `x` with a peak amplitude ``1``.
 """
 sawtoothwave1(x::Real) = rem(x, 1.0, RoundNearest) * 2
 
+sawtoothwave1(::Missing) = missing
+
 end # module

test/runtests.jl

@@ -8,39 +8,51 @@ const θ = 0.05
     @testset "squarewave" begin
         @test squarewave(x) == 1.0
         @test squarewave(y) == 1.0
+        @test isequal(squarewave(missing), missing)
         @test squarewave(x, θ) == -1.0
         @test squarewave(y, θ) == -1.0
         @test_throws DomainError squarewave(x, -1.0)
         @test_throws DomainError squarewave(x, 2.0)
+        @test isequal(squarewave(missing, θ), missing)
+        @test isequal(squarewave(x, missing), missing)
+        @test isequal(squarewave(missing, missing), missing)
     end
     @testset "squarewave1" begin
         @test squarewave1(x) == 1.0
         @test squarewave1(y) == 1.0
+        @test isequal(squarewave1(missing), missing)
         @test squarewave1(x, θ) == -1.0
         @test squarewave1(y, θ) == -1.0
         @test_throws DomainError squarewave1(x, -1.0)
         @test_throws DomainError squarewave1(x, 2.0)
+        @test isequal(squarewave1(missing, θ), missing)
+        @test isequal(squarewave1(x, missing), missing)
+        @test isequal(squarewave1(missing, missing), missing)
     end
 end
 
 @testset "triangle waves" begin
     @testset "trianglewave" begin
         @test trianglewave(x) == 0.2546479089470326
         @test trianglewave(y) == 0.8571428571428572
+        @test isequal(trianglewave(missing), missing)
     end
     @testset "trianglewave1" begin
         @test trianglewave1(x) == 0.3999999999999999
         @test trianglewave1(y) == 0.6144125938460689
+        @test isequal(trianglewave1(missing), missing)
     end
 end
 
 @testset "sawtooth waves" begin
     @testset "sawtoothwave" begin
         @test sawtoothwave(x) == 0.12732395447351627
         @test sawtoothwave(y) == 0.42857142857142855
+        @test isequal(sawtoothwave(missing), missing)
     end
     @testset "sawtoothwave1" begin
         @test sawtoothwave1(x) == 0.8
         @test sawtoothwave1(y) == 0.6927937030769655
+        @test isequal(sawtoothwave1(missing), missing)
     end
 end