Examples with ExprPolynomialRing org.matheclipse.core.polynomials.longexponent.ExprPolynomialRing used on opensource projects

Example 11 with ExprPolynomialRing

use of org.matheclipse.core.polynomials.longexponent.ExprPolynomialRing in project symja_android_library by axkr.

the class RootsFunctions method coefficients.

/**
 * Get the coefficient list of a univariate polynomial.
 *
 * @param polynomial
 * @param variable
 * @return <code>null</code> if the list couldn't be evaluated.
 */
public static double[] coefficients(IExpr polynomial, final ISymbol variable) throws JASConversionException {
    try {
        ExprPolynomialRing ring = new ExprPolynomialRing(F.list(variable));
        ExprPolynomial poly = ring.create(polynomial);
        IAST list = poly.coefficientList();
        int degree = list.size() - 2;
        double[] result = new double[degree + 1];
        for (int i = 1; i < list.size(); i++) {
            ISignedNumber temp = list.get(i).evalReal();
            if (temp != null) {
                result[i - 1] = temp.doubleValue();
            } else {
                return null;
            }
        }
        return result;
    } catch (RuntimeException ex) {
        // Polynomial expected!
        return null;
    }
}

Example 12 with ExprPolynomialRing

use of org.matheclipse.core.polynomials.longexponent.ExprPolynomialRing in project symja_android_library by axkr.

the class RootsFunctions method rootsOfQuadraticExprPolynomial.

/**
 * Solve a polynomial with degree <= 2.
 *
 * @param expr
 * @param varList
 * @return <code>F.NIL</code> if no evaluation was possible.
 */
private static IAST rootsOfQuadraticExprPolynomial(final IExpr expr, IAST varList) {
    IASTMutable result = F.NIL;
    try {
        // try to generate a common expression polynomial
        ExprPolynomialRing ring = new ExprPolynomialRing(ExprRingFactory.CONST, varList);
        ExprPolynomial ePoly = ring.create(expr, false, false, false);
        ePoly = ePoly.multiplyByMinimumNegativeExponents();
        result = rootsOfQuadraticPolynomial(ePoly);
        if (result.isPresent() && expr.isNumericMode()) {
            for (int i = 1; i < result.size(); i++) {
                result.set(i, F.chopExpr(result.get(i), Config.DEFAULT_ROOTS_CHOP_DELTA));
            }
        }
        result = QuarticSolver.sortASTArguments(result);
        return result;
    } catch (JASConversionException e2) {
        LOGGER.debug("RootsFunctions.rootsOfQuadraticExprPolynomial() failed", e2);
    }
    return result;
}