added first test

Author: mboberg

src/MPISphericalHarmonics.jl

@@ -8,11 +8,14 @@ using MPIMagneticFields
 using SphericalHarmonicExpansions
 using MPIFiles
 
+export MagneticFieldCoefficients
+
+# Spherical harmonic coefficients describing a magnetic field
 mutable struct MagneticFieldCoefficients
-  coeffs::Array{SphericalHarmonicCoefficients,2}
-  radius::Float64
-  center::Vector{Float64}
-  ffp::Union{Array{Float64,2},Nothing}
+  coeffs::Array{SphericalHarmonicCoefficients,2} # coefficients
+  radius::Float64 # radius of measured sphere
+  center::Vector{Float64} # center of measured sphere
+  ffp::Union{Array{Float64,2},Nothing} # field-free-point (if available)
 
   function MagneticFieldCoefficients(coeffs::Array{SphericalHarmonicCoefficients,2}, radius::Float64,
   				     center::Vector{Float64}, ffp::Union{Array{Float64,2},Nothing})
@@ -94,7 +97,7 @@ end
 """
 function magneticField(tDesign::SphericalTDesign, field::Union{AbstractArray{T,2},AbstractArray{T,3}}, 
 		       x::Variable, y::Variable, z::Variable;
-		       L::Int=Int(floor(tDesign.T/2)),
+		       L::Int=floor(Int,tDesign.T/2),
 		       calcSolid::Bool=true) where T <: Real
 
   # get tDesign positions [m] and removing the unit
@@ -208,4 +211,4 @@ MPIMagneticFields.value(field::SphericalHarmonicDefinedField, r) = [MPIMagneticF
 
 selectPatch(field::SphericalHarmonicDefinedField, patchNum) = field.patch = patchNum
 
-end
+end

test/runtests.jl

@@ -1,4 +1,6 @@
 using MPISphericalHarmonics
+using MPIMagneticFields
+using MPIFiles 
 using Test
 using Aqua
 
@@ -7,5 +9,31 @@ using Aqua
     Aqua.test_all(MPISphericalHarmonics, ambiguities=false)
   end
 
+ 
+  @testset "Ideal Coefficents" begin
+
+    ## Calculate some field values
+    # load a spherical t-design
+    tDes = loadTDesign(6,26,42u"mm")
+    # ideal gradient field with FFP
+    idealField = IdealFFP([-1,-1,2])
+    # get field values
+    fieldValues = hcat([idealField[ustrip.(Unitful.m.(pos))...] for pos in tDes]...)
+
+    ## Calculate coefficients
+    MPISphericalHarmonics.@polyvar x y z
+    coeffs, = MPISphericalHarmonics.magneticField(tDes, fieldValues, x,y,z)
+
+    ## Test coefficients
+    numCoeffs = length(coeffs[1,1].c)
+    # ideal coefficients
+    ideal = [zeros(numCoeffs) for j=1:3]
+    ideal[1][4] = ideal[2][2] = idealField.gradient[1] # gradient (x,y)
+    ideal[3][3] = idealField.gradient[3] # gradient (z)
+    for j=1:3
+      @test isapprox(coeffs[j,1].c, ideal[j], atol = 1e-10)
+    end
+
+  end
 
 end