问题
I have 2D jagged array. And I want to sort it by any rows.
I've searched and found code for sorting by columns
private static void Sort<T>(T[][] data, int col)
{
Comparer<T> comparer = Comparer<T>.Default;
Array.Sort<T[]>(data, (x,y) => comparer.Compare(x[col],y[col]));
}
Can I adapt it for sort by any rows ?
Any help is appreciated.
Sample of my jagged array (Added)
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication3
{
class Program
{
static void Main(string[] args)
{
int n = 10;
int[][] capm = new int[3][];
for (int i = 0; i <= 2; i++)
{
capm[i] = new int[n + 1];
}
Random rand = new Random();
for (int i = 1; i <= n; i++)
{
capm[1][i] = i;
}
for (int i = 1; i <= n; i++)
{
capm[2][i] = rand.Next(1, 6);
}
Sort(capm, 2);
Console.ReadLine();
}
private static void Sort<T>(T[][] data, int col)
{
data = data.OrderBy(i => i[col]).ToArray();
}
}
}
@Dani & @Martin I want my jagged array to sort by capm[2][].
回答1:
The only way I can think of doing this is sorting by an array of indices:
private static void Sort<T>(T[][] data, int row)
{
int[] Indices = new int[data[0].Length];
for(int i = 0; i < Indices.Length; i++)
Indices[i] = i;
Comparer<T> comparer = Comparer<T>.Default;
Array.Sort(Indices, (x, y) => comparer.Compare(data[row][x], data[row][y]);
for(int i = 0; i < data.Length; i++)
{
T[] OldRow = (T[])data[i].Clone();
for(int j = 0; j < OldRow.Length; j++)
data[i][j] = OldRow[i][Indices[j]];
}
}
回答2:
Given you are using a jagged array this will sort it by the 3rd item.. but a 2D array is probably better if you want to guarantee that each row has the same number of columns... If you have an array within the array which doesn't have a 3rd column, this will fail!
private static void Sort<T>(T[][] data, int col)
{
data = data.OrderBy(i => i[col]).ToArray();
}
Edit:
In order to do anything with the new data reference you either need to return it or pass the parameter by reference:
private static void Sort<T>(ref T[][] data, int col)
{
data = data.OrderBy(i => i[col]).ToArray();
}
The array itself isn't sorted, a new sorted array is created
来源:https://stackoverflow.com/questions/8162348/how-do-i-sort-jagged-array-by-row-in-c