static int searchAscending()

in commons-statistics-inference/src/main/java/org/apache/commons/statistics/inference/Searches.java [92:125]

• 26 lines of code
• 8 McCabe index (conditional complexity)

    static int searchAscending(int a, int b, double x, IntToDoubleFunction value) {
        // Use a binary search for a large range.
        if (b - a > BINARY_SEARCH) {
            // Edge case as the search never evaluates the end points.
            if (value.applyAsDouble(a) > x) {
                return a - 1;
            }
            if (value.applyAsDouble(b) <= x) {
                return b;
            }

            // value(lo) is always <= x
            // value(hi) is always > x
            int lo = a;
            int hi = b;
            while (lo + 1 < hi) {
                final int mid = (lo + hi) >>> 1;
                if (value.applyAsDouble(mid) <= x) {
                    lo = mid;
                } else {
                    hi = mid;
                }
            }
            return lo;
        }

        // Sequential search
        int i = a - 1;
        // Evaluate between [a, b]
        while (i < b && value.applyAsDouble(i + 1) <= x) {
            i++;
        }
        return i;
    }