public override ECFieldElement Add(
ECFieldElement b)
{
// No check performed here for performance reasons. Instead the
// elements involved are checked in ECPoint.F2m
// checkFieldElements(this, b);
LongArray iarrClone = this.x.Copy();
F2mFieldElement bF2m = (F2mFieldElement)b;
iarrClone.AddShiftedByWords(bF2m.x, 0);
return(new F2mFieldElement(m, ks, iarrClone));
}
public override bool Equals(
object obj)
{
if (obj == this)
{
return(true);
}
F2mFieldElement other = obj as F2mFieldElement;
if (other == null)
{
return(false);
}
return(Equals(other));
}
/**
* Checks, if the ECFieldElements <code>a</code> and <code>b</code>
* are elements of the same field <code>F<sub>2<sup>m</sup></sub></code>
* (having the same representation).
* @param a field element.
* @param b field element to be compared.
* @throws ArgumentException if <code>a</code> and <code>b</code>
* are not elements of the same field
* <code>F<sub>2<sup>m</sup></sub></code> (having the same
* representation).
*/
public static void CheckFieldElements(
ECFieldElement a,
ECFieldElement b)
{
if (!(a is F2mFieldElement) || !(b is F2mFieldElement))
{
throw new ArgumentException("Field elements are not "
+ "both instances of F2mFieldElement");
}
F2mFieldElement aF2m = (F2mFieldElement)a;
F2mFieldElement bF2m = (F2mFieldElement)b;
if (aF2m.representation != bF2m.representation)
{
// Should never occur
throw new ArgumentException("One of the F2m field elements has incorrect representation");
}
if ((aF2m.m != bF2m.m) || !Arrays.AreEqual(aF2m.ks, bF2m.ks))
{
throw new ArgumentException("Field elements are not elements of the same field F2m");
}
}