c# - 计算多个不同的值 - Linq

Question

我有一个点列表（每个点都有id,x,y,z属性）。

我想获得属性的总不同值x,y,z

我在做：

var points = new List<MyPoint>
{
    new MyPoint {Id = 0, X = 97.5, Y = 92.5, Z = -16.6666660308838},
    new MyPoint {Id = 1, X = 292.5, Y = 92.5, Z = -16.6666660308838},
    new MyPoint {Id = 2, X = 97.5, Y = 277.5, Z = -16.6666660308838},
    new MyPoint {Id = 3, X = 292.5, Y = 277.5, Z = -16.6666660308838},
    new MyPoint {Id = 4, X = 97.5, Y = 462.5, Z = -16.6666660308838},
    new MyPoint {Id = 5, X = 292.5, Y = 462.5, Z = -16.6666660308838},
    new MyPoint {Id = 6, X = 97.5, Y = 92.5, Z = -49.9999980926514},
    new MyPoint {Id = 7, X = 292.5, Y = 92.5, Z = -49.9999980926514},
    new MyPoint {Id = 8, X = 97.5, Y = 277.5, Z = -49.9999980926514},
    new MyPoint {Id = 9, X = 292.5, Y = 277.5, Z = -49.9999980926514},
    new MyPoint {Id = 10, X = 97.5, Y = 462.5, Z = -49.9999980926514},
    new MyPoint {Id = 11, X = 292.5, Y = 462.5, Z = -49.9999980926514},
    new MyPoint {Id = 12, X = 97.5, Y = 92.5, Z = -83.3333320617676},
    new MyPoint {Id = 13, X = 292.5, Y = 92.5, Z = -83.3333320617676},
    new MyPoint {Id = 14, X = 97.5, Y = 277.5, Z = -83.3333320617676},
    new MyPoint {Id = 15, X = 292.5, Y = 277.5, Z = -83.3333320617676},
    new MyPoint {Id = 16, X = 97.5, Y = 462.5, Z = -83.3333320617676},
    new MyPoint {Id = 17, X = 292.5, Y = 462.5, Z = -83.3333320617676}
};
var result =
    points
    .GroupBy(l => l.Id)
    .Select(g => new
    {
        sizeX = g.Select(l => l.X).Distinct().Count(),
        sizeY = g.Select(l => l.Y).Distinct().Count(),
        sizeZ = g.Select(l => l.Z).Distinct().Count()
    });

我得到这个：

我该如何解决这个问题，所以我得到

X ->2
Y ->3
Z ->3

?

标签： c#performancelinq

Answer 1

是否遵循您的需要？

var result = new
{
    sizeX = points.Select(l => l.X).Distinct().Count(),
    sizeY = points.Select(l => l.Y).Distinct().Count(),
    sizeZ = points.Select(l => l.Z).Distinct().Count()
};