fixed? motor composition by matching where motor identity should be

src/motor3D.jl

@@ -38,10 +38,10 @@ function Base.:(*)(a::Motor3D, b::Motor3D)
         a[4] * b[2] + a[2] * b[4] + a[3] * b[1] - a[1] * b[3],
         a[4] * b[3] + a[3] * b[4] + a[1] * b[2] - a[2] * b[1],
         a[4] * b[4] - a[1] * b[1] - a[2] * b[2] - a[3] * b[3],
-        a[8] * b[3] + a[5] * b[2] - a[6] * b[1] + a[7] * b[4] + b[8] * a[3] - b[6] * a[2] + b[7] * a[1] + b[5] * a[4],
-        a[8] * b[1] + a[5] * b[4] + a[6] * b[3] - a[7] * b[2] + b[8] * a[1] + b[6] * a[4] - b[7] * a[3] + b[5] * a[2],
-        a[8] * b[2] - a[5] * b[3] + a[6] * b[4] + a[7] * b[1] + b[8] * a[2] + b[6] * a[3] + b[7] * a[4] - b[5] * a[1],
-        a[8] * b[4] - a[5] * b[1] - a[6] * b[2] - a[7] * b[3] + b[8] * a[4] - b[6] * a[1] - b[7] * a[2] - b[5] * a[3]
+        a[8] * b[3] + a[6] * b[2] - a[7] * b[1] + a[5] * b[4] + b[8] * a[3] - b[6] * a[2] + b[7] * a[1] + b[5] * a[4],
+        a[8] * b[1] + a[6] * b[4] + a[7] * b[3] - a[5] * b[2] + b[8] * a[1] + b[6] * a[4] - b[7] * a[3] + b[5] * a[2],
+        a[8] * b[2] - a[6] * b[3] + a[7] * b[4] + a[5] * b[1] + b[8] * a[2] + b[6] * a[3] + b[7] * a[4] - b[5] * a[1],
+        a[8] * b[4] - a[6] * b[1] - a[7] * b[2] - a[5] * b[3] + b[8] * a[4] - b[6] * a[1] - b[7] * a[2] - b[5] * a[3]
     )
 end
 #=

test/test_motor3D.jl

@@ -94,16 +94,16 @@ end
         using PGA3D, Test, SafeTestsets, Logging, PrettyPrinting, StaticArrays, Random, LinearAlgebra
         @testset "Motor Identity" begin
             motoridentity = identity_motor()
-            for i in 1:3
+            for i in 1:100
                 testfrom = Point3D(randn(3)...)
                 testto = Point3D(randn(3)...)
                 testline = line_fromto(testfrom, testto)
                 testangle = randn()
                 testdisp = randn()
                 testmotor = motor_screw(testline, testangle, testdisp)
 
-                #@test testmotor * motoridentity ≈ testmotor
-                #@test motoridentity * testmotor ≈ testmotor
+                @test testmotor * motoridentity ≈ testmotor
+                @test motoridentity * testmotor ≈ testmotor
             end
         end
     end