C# Online Compiler | .NET Fiddle

<no name> by Anonymous

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

public class Meh
{
	public static void Main()
	{
		static bool IsEven(int x)
		{
			Console.WriteLine($"{x} -> IsEven was executed!");
			return x % 2 == 0;
		}

		static bool IsOdd(int x)
		{
			Console.WriteLine($"{x} -> IsOdd was executed!");
			return x % 2 == 0;
		}

		var lookup = GetEnumerable(10).Where(IsEven).ToLookup(IsOdd);
	}

	static IEnumerable<int> GetEnumerable(int i)
	{
		return Enumerable.Range(0, i);
	}
}

​x
 
using System;
using System.Collections.Generic;
using System.Linq;  
​
public class Meh
{
    public static void Main()
    {
        static bool IsEven(int x)
        {
            Console.WriteLine($"{x} -> IsEven was executed!");
            return x % 2 == 0;
        }
​
        static bool IsOdd(int x)
        {
            Console.WriteLine($"{x} -> IsOdd was executed!");
            return x % 2 == 0;
        }
​
        var lookup = GetEnumerable(10).Where(IsEven).ToLookup(IsOdd);
    }
​
    static IEnumerable<int> GetEnumerable(int i)
    {
        return Enumerable.Range(0, i);
    }
}
​

Matriz original (7x7 con términos independientes):
6    10    6    10    -7    6    -6    -4
-7    -3    6    -9    5    10    10    -10
-3    1    1    -8    -9    8    -9    6
10    -2    2    0    2    0    -10    -5
-8    3    -1    8    -3    5    4    -7
-9    -5    2    4    -2    0    -3    -1
5    -8    -6    -8    -2    3    -6    5

Matriz final después de la eliminación de Gauss:
10    -2    2    0    2    0    -10    -5
0    11.2    4.8    10    -8.2    6    0    -1
0    0    9.285714285714286    -5.071428571428571    3.178571428571429    12.357142857142858    3    -13.892857142857142
0    0    0    13.73846153846154    -7.476923076923077    -5.292307692307692    -14.169230769230769    3.938461538461537
0    0    0    0    -12.71976483762598    2.9658454647256445    -20.276035834266516    8.84518477043673
0    8.881784197001252E-16    0    0    4.440892098500626E-16    8.482865632221854    10.416837240013205    -4.168620006602838
0    0    0    0    0    0    -11.652915398566236    -6.77198711013209

La solución del sistema es:
x1 = 0.3365242565830708
x2 = -0.38994306713824967
x3 = 0.23588117352499516
x4 = -0.6137042986871154
x5 = -1.9027404366930845
x6 = -1.2050493124972865
x7 = 0.5811410173771029

Last Run:	6:38:29 am
Compile:	0.008s
Execute:	0.07s
Memory:	2.97Mb
CPU:	0.078s

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