added structures

src/AstroHelper.jl

@@ -1,7 +1,8 @@
 module AstroHelper
 using LinearAlgebra
-
+using DataFrames
 
 include("quaternions.jl")
+include("aeStructures.jl")
 
 end # module

src/aeStructures.jl

@@ -0,0 +1,30 @@
+struct Section
+    data::DataFrame
+    xc::Float64
+    yc::Float64
+    Ixx::Float64
+    Iyy::Float64
+    Ixy::Float64
+
+    function Section(A, x, y)
+        d = DataFrame(A=A, x=x, y=y)
+
+        d.Ax = d.A .* d.x
+        d.Ay = d.A .* d.y
+
+        xc = sum(d.Ax) / sum(d.A)
+        yc = sum(d.Ay) / sum(d.A)
+
+        Ixx = sum(d.A .* ((d.y .- yc).^2))
+        Iyy = sum(d.A .* ((d.x .- xc).^2))
+        Ixy = sum(d.A .* ((d.x .- xc) .* (d.y .- yc)))
+
+
+        new(d, xc, yc, Ixx, Iyy, Ixy)
+
+    end 
+
+
+end
+
+