Question

I wrote a function which does this functionality and I am not satisfied with the performance & implementation. I wanted to see if someone can help me implement this nifty functionality in an efficient way.

The function should return a string which is the average time between 2 timer values passed. 2 timer values are both strings of the format "MM:SS:HS" for example if values "02:02:20" and "04:04:40" are passed to the function it should output the average time between those values and return it as a string in the same format "03.03.30".

I wanted to implement it in C#, Java is fine too.

Look forward to your solutions. Thanks for reading!

Answer 1

• Use TimeSpan.Parse to parse the two values
• Add them together
• Take the number of ticks of the sum (TimeSpan.Ticks) and divide it by two to get the average (as you can’t divide a TimeSpan directly)
• Use TimeSpan.FromTicks to convert back to a TimeSpan
• Call ToString to convert back from a TimeSpan to a string.

(I’m not sure why the other answers are suggesting subtraction, when a mean value is usually gained by adding values and then dividing…)

Personally I’d probably split this into two methods, one of which just did the averaging part, and the other of which did the text conversions:

public static TimeSpan Average(TimeSpan first, TimeSpan second)
{
    return TimeSpan.FromTicks((first + second).Ticks / 2);
}

public static string Average(string first, string second)
{
    TimeSpan firstSpan = TimeSpan.Parse(first);
    TimeSpan secondSpan = TimeSpan.Parse(second);
    return Average(firstSpan, secondSpan).ToString();
}

You may need to mess around a bit to get the exact text format you want – there are more options in .NET 4 than previously, using ToString with a format string etc.