group values by time.cs

group values by time.cs

using System;
using System.Collections.Generic;
using System.Linq;

var series = new List<Sample>();
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(-3) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(0) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(3) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(4) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(5) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(6) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(7) });
series.Add(new (){ timestamp = DateTime.Now.AddMinutes(15) });

var groups = series.GroupBy(x =>
{
    var ticks = TimeSpan.FromMinutes(5).Ticks;
    var stamp = x.timestamp.Ticks % ticks;
    return x.timestamp.AddTicks(-stamp + ticks);
})
.ToList();

foreach(var g in groups)
{
    Console.WriteLine(g.Key);
    foreach(var x in g)
    {
        Console.WriteLine(x);
    }
    Console.WriteLine();
}


public record class Sample
{
    public DateTime timestamp;
}

output

09/10/2024 17:30:00
Sample { timestamp = 09/10/2024 17:28:05 }

09/10/2024 17:35:00
Sample { timestamp = 09/10/2024 17:31:05 }
Sample { timestamp = 09/10/2024 17:34:05 }

09/10/2024 17:40:00
Sample { timestamp = 09/10/2024 17:35:05 }
Sample { timestamp = 09/10/2024 17:36:05 }
Sample { timestamp = 09/10/2024 17:37:05 }
Sample { timestamp = 09/10/2024 17:38:05 }

09/10/2024 17:50:00
Sample { timestamp = 09/10/2024 17:46:05 }