/// <param name="field">the {@link GF256} instance representing the field to use
/// to perform computations
/// </param>
/// <param name="coefficients">coefficients as ints representing elements of GF(256), arranged
/// from most significant (highest-power term) coefficient to least significant
/// </param>
/// <throws> IllegalArgumentException if argument is null or empty, </throws>
/// <summary> or if leading coefficient is 0 and this is not a
/// constant polynomial (that is, it is not the monomial "0")
/// </summary>
internal GF256Poly(GF256 field, int[] coefficients)
{
if (coefficients == null || coefficients.Length == 0)
{
throw new ArgumentException();
}
this.field = field;
int coefficientsLength = coefficients.Length;
if (coefficientsLength > 1 && coefficients[0] == 0)
{
// Leading term must be non-zero for anything except the constant polynomial "0"
int firstNonZero = 1;
while (firstNonZero < coefficientsLength && coefficients[firstNonZero] == 0)
{
firstNonZero++;
}
if (firstNonZero == coefficientsLength)
{
this.coefficients = field.Zero.coefficients;
}
else
{
this.coefficients = new int[coefficientsLength - firstNonZero];
Array.Copy(coefficients, firstNonZero, this.coefficients, 0, this.coefficients.Length);
}
}
else
{
this.coefficients = coefficients;
}
}
public ReedSolomonEncoder(GF256 field)
{
if (!GF256.QR_CODE_FIELD.Equals(field))
{
throw new ArgumentException("Only QR Code is supported at this time");
}
this.field = field;
cachedGenerators = new List<GF256Poly>(10);
cachedGenerators.Add(new GF256Poly(field, new[] {1}));
}