"use strict";
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/*
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* Copyright 2007 ZXing authors
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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Object.defineProperty(exports, "__esModule", { value: true });
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/*namespace com.google.zxing.common.reedsolomon {*/
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var AbstractGenericGF_1 = require("./AbstractGenericGF");
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var System_1 = require("../../util/System");
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var IllegalArgumentException_1 = require("../../IllegalArgumentException");
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/**
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* <p>Represents a polynomial whose coefficients are elements of a GF.
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* Instances of this class are immutable.</p>
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*
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* <p>Much credit is due to William Rucklidge since portions of this code are an indirect
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* port of his C++ Reed-Solomon implementation.</p>
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*
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* @author Sean Owen
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*/
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var GenericGFPoly = /** @class */ (function () {
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/**
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* @param field the {@link GenericGF} instance representing the field to use
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* to perform computations
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* @param coefficients coefficients as ints representing elements of GF(size), arranged
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* from most significant (highest-power term) coefficient to least significant
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* @throws IllegalArgumentException if argument is null or empty,
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* or if leading coefficient is 0 and this is not a
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* constant polynomial (that is, it is not the monomial "0")
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*/
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function GenericGFPoly(field, coefficients) {
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if (coefficients.length === 0) {
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throw new IllegalArgumentException_1.default();
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}
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this.field = field;
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var coefficientsLength = coefficients.length;
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if (coefficientsLength > 1 && coefficients[0] === 0) {
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// Leading term must be non-zero for anything except the constant polynomial "0"
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var firstNonZero = 1;
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while (firstNonZero < coefficientsLength && coefficients[firstNonZero] === 0) {
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firstNonZero++;
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}
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if (firstNonZero === coefficientsLength) {
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this.coefficients = Int32Array.from([0]);
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}
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else {
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this.coefficients = new Int32Array(coefficientsLength - firstNonZero);
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System_1.default.arraycopy(coefficients, firstNonZero, this.coefficients, 0, this.coefficients.length);
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}
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}
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else {
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this.coefficients = coefficients;
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}
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}
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GenericGFPoly.prototype.getCoefficients = function () {
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return this.coefficients;
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};
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/**
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* @return degree of this polynomial
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*/
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GenericGFPoly.prototype.getDegree = function () {
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return this.coefficients.length - 1;
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};
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/**
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* @return true iff this polynomial is the monomial "0"
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*/
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GenericGFPoly.prototype.isZero = function () {
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return this.coefficients[0] === 0;
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};
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/**
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* @return coefficient of x^degree term in this polynomial
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*/
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GenericGFPoly.prototype.getCoefficient = function (degree /*int*/) {
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return this.coefficients[this.coefficients.length - 1 - degree];
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};
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/**
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* @return evaluation of this polynomial at a given point
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*/
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GenericGFPoly.prototype.evaluateAt = function (a /*int*/) {
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if (a === 0) {
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// Just return the x^0 coefficient
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return this.getCoefficient(0);
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}
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var coefficients = this.coefficients;
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var result;
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if (a === 1) {
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// Just the sum of the coefficients
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result = 0;
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for (var i = 0, length_1 = coefficients.length; i !== length_1; i++) {
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var coefficient = coefficients[i];
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result = AbstractGenericGF_1.default.addOrSubtract(result, coefficient);
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}
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return result;
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}
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result = coefficients[0];
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var size = coefficients.length;
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var field = this.field;
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for (var i = 1; i < size; i++) {
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result = AbstractGenericGF_1.default.addOrSubtract(field.multiply(a, result), coefficients[i]);
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}
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return result;
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};
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GenericGFPoly.prototype.addOrSubtract = function (other) {
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if (!this.field.equals(other.field)) {
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throw new IllegalArgumentException_1.default('GenericGFPolys do not have same GenericGF field');
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}
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if (this.isZero()) {
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return other;
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}
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if (other.isZero()) {
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return this;
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}
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var smallerCoefficients = this.coefficients;
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var largerCoefficients = other.coefficients;
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if (smallerCoefficients.length > largerCoefficients.length) {
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var temp = smallerCoefficients;
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smallerCoefficients = largerCoefficients;
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largerCoefficients = temp;
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}
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var sumDiff = new Int32Array(largerCoefficients.length);
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var lengthDiff = largerCoefficients.length - smallerCoefficients.length;
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// Copy high-order terms only found in higher-degree polynomial's coefficients
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System_1.default.arraycopy(largerCoefficients, 0, sumDiff, 0, lengthDiff);
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for (var i = lengthDiff; i < largerCoefficients.length; i++) {
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sumDiff[i] = AbstractGenericGF_1.default.addOrSubtract(smallerCoefficients[i - lengthDiff], largerCoefficients[i]);
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}
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return new GenericGFPoly(this.field, sumDiff);
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};
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GenericGFPoly.prototype.multiply = function (other) {
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if (!this.field.equals(other.field)) {
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throw new IllegalArgumentException_1.default('GenericGFPolys do not have same GenericGF field');
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}
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if (this.isZero() || other.isZero()) {
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return this.field.getZero();
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}
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var aCoefficients = this.coefficients;
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var aLength = aCoefficients.length;
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var bCoefficients = other.coefficients;
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var bLength = bCoefficients.length;
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var product = new Int32Array(aLength + bLength - 1);
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var field = this.field;
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for (var i = 0; i < aLength; i++) {
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var aCoeff = aCoefficients[i];
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for (var j = 0; j < bLength; j++) {
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product[i + j] = AbstractGenericGF_1.default.addOrSubtract(product[i + j], field.multiply(aCoeff, bCoefficients[j]));
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}
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}
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return new GenericGFPoly(field, product);
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};
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GenericGFPoly.prototype.multiplyScalar = function (scalar /*int*/) {
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if (scalar === 0) {
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return this.field.getZero();
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}
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if (scalar === 1) {
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return this;
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}
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var size = this.coefficients.length;
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var field = this.field;
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var product = new Int32Array(size);
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var coefficients = this.coefficients;
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for (var i = 0; i < size; i++) {
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product[i] = field.multiply(coefficients[i], scalar);
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}
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return new GenericGFPoly(field, product);
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};
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GenericGFPoly.prototype.multiplyByMonomial = function (degree /*int*/, coefficient /*int*/) {
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if (degree < 0) {
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throw new IllegalArgumentException_1.default();
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}
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if (coefficient === 0) {
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return this.field.getZero();
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}
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var coefficients = this.coefficients;
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var size = coefficients.length;
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var product = new Int32Array(size + degree);
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var field = this.field;
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for (var i = 0; i < size; i++) {
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product[i] = field.multiply(coefficients[i], coefficient);
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}
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return new GenericGFPoly(field, product);
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};
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GenericGFPoly.prototype.divide = function (other) {
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if (!this.field.equals(other.field)) {
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throw new IllegalArgumentException_1.default('GenericGFPolys do not have same GenericGF field');
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}
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if (other.isZero()) {
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throw new IllegalArgumentException_1.default('Divide by 0');
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}
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var field = this.field;
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var quotient = field.getZero();
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var remainder = this;
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var denominatorLeadingTerm = other.getCoefficient(other.getDegree());
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var inverseDenominatorLeadingTerm = field.inverse(denominatorLeadingTerm);
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while (remainder.getDegree() >= other.getDegree() && !remainder.isZero()) {
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var degreeDifference = remainder.getDegree() - other.getDegree();
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var scale = field.multiply(remainder.getCoefficient(remainder.getDegree()), inverseDenominatorLeadingTerm);
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var term = other.multiplyByMonomial(degreeDifference, scale);
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var iterationQuotient = field.buildMonomial(degreeDifference, scale);
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quotient = quotient.addOrSubtract(iterationQuotient);
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remainder = remainder.addOrSubtract(term);
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}
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return [quotient, remainder];
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};
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/*@Override*/
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GenericGFPoly.prototype.toString = function () {
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var result = '';
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for (var degree = this.getDegree(); degree >= 0; degree--) {
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var coefficient = this.getCoefficient(degree);
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if (coefficient !== 0) {
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if (coefficient < 0) {
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result += ' - ';
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coefficient = -coefficient;
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}
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else {
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if (result.length > 0) {
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result += ' + ';
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}
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}
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if (degree === 0 || coefficient !== 1) {
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var alphaPower = this.field.log(coefficient);
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if (alphaPower === 0) {
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result += '1';
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}
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else if (alphaPower === 1) {
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result += 'a';
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}
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else {
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result += 'a^';
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result += alphaPower;
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}
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}
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if (degree !== 0) {
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if (degree === 1) {
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result += 'x';
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}
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else {
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result += 'x^';
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result += degree;
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}
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}
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}
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}
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return result;
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};
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return GenericGFPoly;
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}());
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exports.default = GenericGFPoly;
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