public ArrayFieldVector(FieldVector<T> v1,FieldVector<T> v2) throws NullArgumentException {
  MathUtils.checkNotNull(v1);
  MathUtils.checkNotNull(v2);
  field=v1.getField();
  final T[] v1Data=(v1 instanceof ArrayFieldVector) ? ((ArrayFieldVector<T>)v1).data : v1.toArray();
  final T[] v2Data=(v2 instanceof ArrayFieldVector) ? ((ArrayFieldVector<T>)v2).data : v2.toArray();
  data=MathArrays.buildArray(field,v1Data.length + v2Data.length);
  System.arraycopy(v1Data,0,data,0,v1Data.length);
  System.arraycopy(v2Data,0,data,v1Data.length,v2Data.length);
}

public ArrayFieldVector ( FieldVector < T > v1 , FieldVector < T > v2 ) throws NullArgumentException { MathUtils . checkNotNull ( v1 ) ; MathUtils . checkNotNull ( v2 ) ; field = v1 . getField ( ) ; final T [ ] v1Data = ( v1 instanceof ArrayFieldVector ) ? ( ( ArrayFieldVector < T > ) v1 ) . data : v1 . toArray ( ) ; final T [ ] v2Data = ( v2 instanceof ArrayFieldVector ) ? ( ( ArrayFieldVector < T > ) v2 ) . data : v2 . toArray ( ) ; data = MathArrays . buildArray ( field , v1Data . length + v2Data . length ) ; System . arraycopy ( v1Data , 0 , data , 0 , v1Data . length ) ; System . arraycopy ( v2Data , 0 , data , v1Data . length , v2Data . length ) ; }
construct a vector by appending one vector to another vector .
