Nice Label Algorithm for Charts with minimum ticks

Question

I need to calculate the Ticklabels and the Tickrange for charts manually.

I know the \"standard\" algorithm for nice ticks (see http://books.google.de/books?id=fvA7

Answer 1

I needed this algorithm converted to C#, so here it is...

public static class NiceScale {

    public static void Calculate(double min, double max, int maxTicks, out double range, out double tickSpacing, out double niceMin, out double niceMax) {
        range = niceNum(max - min, false);
        tickSpacing = niceNum(range / (maxTicks - 1), true);
        niceMin = Math.Floor(min / tickSpacing) * tickSpacing;
        niceMax = Math.Ceiling(max / tickSpacing) * tickSpacing;
    }

    private static double niceNum(double range, bool round) {
        double pow = Math.Pow(10, Math.Floor(Math.Log10(range)));
        double fraction = range / pow;

        double niceFraction;
        if (round) {
            if (fraction < 1.5) {
                niceFraction = 1;
            } else if (fraction < 3) {
                niceFraction = 2;
            } else if (fraction < 7) {
                niceFraction = 5;
            } else {
                niceFraction = 10;
            }
        } else {
            if (fraction <= 1) {
                niceFraction = 1;
            } else if (fraction <= 2) {
                niceFraction = 2;
            } else if (fraction <= 5) {
                niceFraction = 5;
            } else {
                niceFraction = 10;
            }
        }

        return niceFraction * pow;
    }

}