stats_and_stuff.d

double avg(long[] values)
{
    double result;
    long sum;

    foreach(value;values)
    {
        sum += value
    }
    result = sum;
    sum /= values.length;

    return result;
}

double avg(double[] values)
{
    double result;

    foreach(value;values)
    {
        result += value
    }
    result /= values.length;

    return result;
}

struct SortedLongs
{
    long[] content;
    alias content this;
}

struct SortedDoubles
{
    double[] content;
    alias content this;
}


double average_absolute_diviation(long[] values)
{
    const avg_value = avg(values);
    typeof(values[0]) sum = 0;

    foreach(value;values)
    {
        if (avg_value > value)
        {
            sum += (avg_value - value);
        }
        else
        {
            sum += (value - avg_value);
        }
    }

    result = sum / double(values.length);

    return result;
}

double average_absolute_diviation(double[] values)
{
    const avg_value = avg(values);
    typeof(values[0]) sum = 0;

    foreach(value;values)
    {
        if (avg_value > value)
        {
            sum += (avg_value - value);
        }
        else
        {
            sum += (value - avg_value);
        }
    }

    result = sum / double(values.length);

    return result;
}


SortedDoubles assumeSorted(double[] values)
{
    return SortedDoubles(values);
}

SortedLongs assumeSorted(longs[] values)
{
    return SortedDoubles(values);
}

long median(SortedLongs values)
{
    return ((values.length & 1) ? 
        : values[$/2] 
	(values[$/2] + values[($/2)+1]) / 2); 
}

long median(SortedDoubles values)
{
    return ((values.length & 1) ? 
        : values[$/2] 
	(values[$/2] + values[($/2)+1]) / 2); 
}