diff --git a/src/Geometry.jl b/src/Geometry.jl
index 3e48e0b..e8107ce 100644
--- a/src/Geometry.jl
+++ b/src/Geometry.jl
@@ -5,11 +5,11 @@ export angle2, norm2d, sq_norm2d
 using StaticArrays: SVector
 
 """
-    angle2(a::SVector{2,Real}, b::SVector{2,Real})
+    angle2(a::SVector{2,R}, b::SVector{2,R}) where {R<:Real}
 
 Returns the angle φ from vector a to b while φ ∈ [-π, π].
 """
-function angle2(a::SVector{2,Real}, b::SVector{2,Real})
+function angle2(a::SVector{2,R}, b::SVector{2,R}) where {R<:Real}
     θ_a = atan(a[2], a[1])
     θ_b = atan(b[2], b[1])
 
@@ -18,11 +18,11 @@ function angle2(a::SVector{2,Real}, b::SVector{2,Real})
     return rem2pi(θ, RoundNearest)
 end
 
-function sq_norm2d(v::SVector{2,Real})
+function sq_norm2d(v::SVector{2,R}) where {R<:Real}
     return v[1]^2 + v[2]^2
 end
 
-function norm2d(v::SVector{2,Real})
+function norm2d(v::SVector{2,R}) where {R<:Real}
     return sqrt(sq_norm2d(v))
 end
 
diff --git a/src/Shape.jl b/src/Shape.jl
index c82df91..40fb4f6 100644
--- a/src/Shape.jl
+++ b/src/Shape.jl
@@ -22,8 +22,8 @@ function project_back_from_unit_circle(θ::Real, half_box_len::Real)
 end
 
 function center_of_mass_from_proj_sums(
-    x_proj_sum::SVector{2,Real}, y_proj_sum::SVector{2,Real}, half_box_len::Real
-)
+    x_proj_sum::SVector{2,R}, y_proj_sum::SVector{2,R}, half_box_len::R
+) where {R<:Real}
     # Prevent for example atan(1e-16, 1e-15) != 0 with rounding
     digits = 5
 
@@ -47,7 +47,9 @@ function center_of_mass_from_proj_sums(
     return SVector(COM_x, COM_y)
 end
 
-function center_of_mass(centers::AbstractVector{SVector{2,Real}}, half_box_len::Real)
+function center_of_mass(
+    centers::AbstractVector{SVector{2,R}}, half_box_len::R
+) where {R<:Real}
     x_proj_sum = SVector(0.0, 0.0)
     y_proj_sum = SVector(0.0, 0.0)
 
@@ -72,8 +74,8 @@ function center_of_mass(particles::AbstractVector{Particle}, half_box_len::Real)
 end
 
 function gyration_tensor(
-    particles::AbstractVector{Particle}, half_box_len::Real, COM::SVector{2,Real}
-)
+    particles::AbstractVector{Particle}, half_box_len::R, COM::SVector{2,R}
+) where {R<:Real}
     S11 = 0.0
     S12 = 0.0
     S22 = 0.0
@@ -104,8 +106,8 @@ function gyration_tensor_eigvals_ratio(
 end
 
 function gyration_tensor_eigvecs(
-    particles::AbstractVector{Particle}, half_box_len::Real, COM::SVector{2,Real}
-)
+    particles::AbstractVector{Particle}, half_box_len::R, COM::SVector{2,R}
+) where {R<:Real}
     g_tensor = gyration_tensor(particles, half_box_len, COM)
     eig_vecs = eigvecs(g_tensor)
 
@@ -116,13 +118,13 @@ function gyration_tensor_eigvecs(
 end
 
 function elliptical_distance(
-    v::SVector{2,Real},
-    COM::SVector{2,Real},
-    gyration_tensor_eigvec_to_smaller_eigval::SVector{2,Real},
-    gyration_tensor_eigvec_to_bigger_eigval::SVector{2,Real},
-    goal_gyration_tensor_eigvals_ratio::Real,
-    half_box_len::Real,
-)
+    v::SVector{2,R},
+    COM::SVector{2,R},
+    gyration_tensor_eigvec_to_smaller_eigval::SVector{2,R},
+    gyration_tensor_eigvec_to_bigger_eigval::SVector{2,R},
+    goal_gyration_tensor_eigvals_ratio::R,
+    half_box_len::R,
+) where {R<:Real}
     v′ = ReCo.minimum_image(v - COM, half_box_len)
 
     x = dot(v′, gyration_tensor_eigvec_to_bigger_eigval)