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+// array functions
+// by david powell 
+// licence LGPL V2 or later 
+//
+// this lib provides 2 functions 
+// Cubic_Array() , and Radial_Array()
+//
+//Cubic_Array(sx,sy,sz,nx,ny,nz,center){childobject}
+//  produces a cubic grid of child objects 
+//  sx,sy,sz = spacing for each axis 
+//  nx,ny,nz and number of objects on each axis 
+//  center = true/false on if geometery is centered or not 
+//
+//
+//Radial_Array(a,n,r){child object}
+// produces a clockwise radial array of child objects rotated around the local z axis   
+// a= interval angle 
+// n= number of objects 
+// r= radius distance 
+//
+// remove // from following line to run test 
+//Cubic_and_Radial_Array_Test();
+
+module Cubic_and_Radial_Array_Test()
+  {
+//center referance point 
+ 	translate([0,0,0])
+	#cube([5,5,5],center=true);
+
+//cubic array  of  5*5*5 objects spaced 10*10*10 center relative
+ 	Cubic_Array(10,10,10,5,5,5,center=true)
+		{
+		sphere(2.5,center=true,$fn=60);
+		}
+
+//a linear array allong x can be derived from the cubic array simply 
+	translate([60,0,0])
+   Cubic_Array(10,0,0,5,1,1,center=false)
+		{
+		cube([5,5,5],center=true);
+		} 
+//a linear array allong y can be derived from the cubic array simply 
+	translate([0,60,0])
+   Cubic_Array(0,10,0,1,5,1,center=false)
+		{
+		cube([5,5,5],center=true);
+		} 
+
+//a linear array allong z can be derived from the cubic array simply 
+	translate([0,0,60])
+   Cubic_Array(0,0,10,1,1,5,center=false)
+		{
+		cube([5,5,5],center=true);
+		} 
+
+//a grid  array allong x,y can be derived from the cubic array simply 
+	translate([0,0,-60])
+   Cubic_Array(10,10,0,5,5,1,center=true)
+		{
+		cube([5,5,5],center=true);
+		} 
+
+//radial array of 32 objects rotated though 10 degrees 
+ 	translate([0,0,0])
+ 	Radial_Array(10,32,40)
+		{
+		cube([2,4,6],center=true);
+		}
+
+// a radial array of linear arrays 
+
+ 	rotate([45,45,45])
+  	Radial_Array(10,36,40)
+		{
+		translate([0,10,0])
+   	Cubic_Array(0,10,0,1,5,1,center=false)
+			{
+			cube([2,3,4],center=true);
+			}
+		}
+
+}
+
+
+// main lib modules
+module Cubic_Array(sx,sy,sz,nx,ny,nz,center)
+	{
+	if (center==true)
+		{
+		translate([-(((nx+1)*sx)/2),-(((ny+1)*sy)/2),-(((nz+1)*sz)/2)])
+			{
+			for(x=[1:nx])
+				{
+				for(y=[1:ny])
+					{
+					for(z=[1:nz])
+						{
+						translate([x*sx,y*sy,z*sz])
+						child(center=true);
+						}
+					}
+				}
+			}
+		}
+	else
+		{
+		translate([0,0,0])
+			{
+			for(x=[1:nx])
+				{
+				for(y=[1:ny])
+					{
+					for(z=[1:nz])
+						{
+						translate([x*sx,y*sy,z*sz])
+						child();
+						}
+					}
+				}
+			}
+		}
+	}
+
+//
+//Radial_Array(a,n,r){child object}
+// produces a clockwise radial array of child objects rotated around the local z axis   
+// a= interval angle 
+// n= number of objects 
+// r= radius distance 
+//
+module Radial_Array(a,n,r)
+{
+ for (k=[0:n-1])
+ {
+ rotate([0,0,-(a*k)])
+ translate([0,r,0])
+ child();
+ }
+}