public void search()

in commons-math-legacy/src/main/java/org/apache/commons/math4/legacy/optim/univariate/BracketFinder.java [116:215]
88 lines of code
16 McCabe index (conditional complexity)

    public void search(UnivariateFunction func,
                       GoalType goal,
                       double xA,
                       double xB) {
        final FunctionEvaluator eval = new FunctionEvaluator(func);
        final boolean isMinim = goal == GoalType.MINIMIZE;

        double fA = eval.value(xA);
        double fB = eval.value(xB);
        if (isMinim ?
            fA < fB :
            fA > fB) {

            double tmp = xA;
            xA = xB;
            xB = tmp;

            tmp = fA;
            fA = fB;
            fB = tmp;
        }

        double xC = xB + GOLD * (xB - xA);
        double fC = eval.value(xC);

        while (isMinim ? fC < fB : fC > fB) {
            double tmp1 = (xB - xA) * (fB - fC);
            double tmp2 = (xB - xC) * (fB - fA);

            double val = tmp2 - tmp1;
            double denom = JdkMath.abs(val) < EPS_MIN ? 2 * EPS_MIN : 2 * val;

            double w = xB - ((xB - xC) * tmp2 - (xB - xA) * tmp1) / denom;
            double wLim = xB + growLimit * (xC - xB);

            double fW;
            if ((w - xC) * (xB - w) > 0) {
                fW = eval.value(w);
                if (isMinim ?
                    fW < fC :
                    fW > fC) {
                    xA = xB;
                    xB = w;
                    fA = fB;
                    fB = fW;
                    break;
                } else if (isMinim ?
                           fW > fB :
                           fW < fB) {
                    xC = w;
                    fC = fW;
                    break;
                }
                w = xC + GOLD * (xC - xB);
                fW = eval.value(w);
            } else if ((w - wLim) * (wLim - xC) >= 0) {
                w = wLim;
                fW = eval.value(w);
            } else if ((w - wLim) * (xC - w) > 0) {
                fW = eval.value(w);
                if (isMinim ?
                    fW < fC :
                    fW > fC) {
                    xB = xC;
                    xC = w;
                    w = xC + GOLD * (xC - xB);
                    fB = fC;
                    fC =fW;
                    fW = eval.value(w);
                }
            } else {
                w = xC + GOLD * (xC - xB);
                fW = eval.value(w);
            }

            xA = xB;
            fA = fB;
            xB = xC;
            fB = fC;
            xC = w;
            fC = fW;
        }

        lo = xA;
        fLo = fA;
        mid = xB;
        fMid = fB;
        hi = xC;
        fHi = fC;

        if (lo > hi) {
            double tmp = lo;
            lo = hi;
            hi = tmp;

            tmp = fLo;
            fLo = fHi;
            fHi = tmp;
        }
    }