AB3: BodyForceTreeMap working

src/Vector3.java

@@ -94,6 +94,15 @@ public class Vector3 {
      * in the form "[x,y,z]", e.g., "[1.48E11,0.0,0.0]".
      */
     public String toString() {
-        return String.format("[%f,%f,%f]", x, y, z);
+        return String.format("[%g,%g,%g]", x, y, z);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other.getClass() != Vector3.class) {
+            return false;
+        }
+        Vector3 v = (Vector3) other;
+        return this.x == v.x && this.y == v.y && this.z == v.z;
     }
 }