Method extendedEcDouble

java/lib/src/main/java/io/github/ccxt/Exchange.java:3133–3142

(ExtendedStarknetPoint point)

    }

    private static ExtendedStarknetPoint extendedEcDouble(ExtendedStarknetPoint point)
    {
        if (point.y.mod(EXTENDED_STARKNET_FIELD_PRIME).equals(BigInteger.ZERO)) {
            throw new RuntimeException("Point y coordinate cannot be zero.");
        }
        BigInteger slope = extendedDivMod(BigInteger.valueOf(3).multiply(point.x).multiply(point.x).add(EXTENDED_STARKNET_ALPHA), BigInteger.valueOf(2).multiply(point.y), EXTENDED_STARKNET_FIELD_PRIME);
        BigInteger x = extendedField(slope.multiply(slope).subtract(BigInteger.valueOf(2).multiply(point.x)));
        BigInteger y = extendedField(slope.multiply(point.x.subtract(x)).subtract(point.y));
        return new ExtendedStarknetPoint(x, y);
    }

    private static ExtendedStarknetPoint extendedEcMult(BigInteger scalar, ExtendedStarknetPoint point)
    {