Example usage for org.apache.commons.math3.fraction BigFraction negate

Introduction

In this page you can find the example usage for org.apache.commons.math3.fraction BigFraction negate.

Prototype

public BigFraction negate() 

Source Link

Document

Return the additive inverse of this fraction, returning the result in reduced form.

Usage

From source file:controller.Parser.java

static LP parse(File f) throws FileNotFoundException {
    Scanner s = new Scanner(f);
    Pattern p = Pattern.compile(dvarreg);

    HashMap<String, Integer> x = new HashMap<String, Integer>();
    HashMap<Integer, String> xReverse = new HashMap<Integer, String>();
    int xcol = 0;

    /* Get input size and names of the decision variables. */
    int constraints = -1; // Take the objective function into account.
    while (s.hasNextLine()) {
        String line = s.nextLine();

        if (line.trim().equals(""))
            continue;

        /* //from   w  ww  .j a va2 s  .c o m
         * TODO: Beware, will now accept invalid
         * files with multiple objective functions.
         */
        /*            if (!validConstraint(line) && !validObj(line)) {
        String e = "Unsupported format in file " + f;
        throw new IllegalArgumentException(e);
                    } */

        Matcher m = p.matcher(line);

        while (m.find()) {
            String var = m.group(3);
            if (validVarName(var) && !x.containsKey(var)) {
                x.put(var, xcol);
                xReverse.put(xcol++, var);
            }
        }
        constraints++;
    }

    BigFraction[][] Ndata = new BigFraction[constraints][x.size()];
    for (int i = 0; i < Ndata.length; i++) {
        Arrays.fill(Ndata[i], BigFraction.ZERO);
    }
    BigFraction[] bdata = new BigFraction[constraints];
    BigFraction[] cdata = new BigFraction[x.size()];
    Arrays.fill(cdata, BigFraction.ZERO);

    s = new Scanner(f);

    String obj = s.nextLine();
    Matcher m = p.matcher(obj);

    while (m.find()) {
        String var = m.group(3);
        if (!x.containsKey(var))
            continue;

        String sign = m.group(1);
        if (sign == null)
            sign = "+";

        String coeffStr = m.group(2);
        BigFraction coeff;
        if (coeffStr == null) {
            coeff = BigFraction.ONE;
        } else {
            coeff = new BigFraction(Double.parseDouble(coeffStr));
        }
        if (sign.equals("-"))
            coeff = coeff.negate();

        cdata[x.get(var)] = coeff;
    }

    int row = 0;
    while (s.hasNextLine()) {
        String line = s.nextLine();
        String[] split = line.split("<=");
        if (line.trim().equals(""))
            continue;
        if (split.length != 2) {
            String e = "Unsupported format in file " + f;
            throw new IllegalArgumentException(e);
        }
        m = p.matcher(line);
        bdata[row] = new BigFraction(Double.parseDouble(split[1]));

        while (m.find()) {
            String var = m.group(3);
            if (!x.containsKey(var))
                continue;

            String sign = m.group(1);
            if (sign == null)
                sign = "+";

            String coeffStr = m.group(2);
            BigFraction coeff;
            if (coeffStr == null) {
                coeff = BigFraction.ONE;
            } else {
                coeff = new BigFraction(Double.parseDouble(coeffStr));
            }
            if (sign.equals("-"))
                coeff = coeff.negate();

            Ndata[row][x.get(var)] = coeff;
        }
        row++;
    }

    return new LP(new Array2DRowFieldMatrix<BigFraction>(Ndata), new ArrayFieldVector<BigFraction>(bdata),
            new ArrayFieldVector<BigFraction>(cdata), xReverse);
}

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From source file:cc.redberry.core.number.Numeric.java

@Override
public Numeric subtract(BigFraction fraction) {
    return add(fraction.negate());
}

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