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How to dynamically create multiple arrays [5,5] , and fill them with random numbers

How to create and fill multiple arrays [5,5], and print it to console.
for now i have that, but i cant get how to dynamically create arrays.
incoming value - for example 3, its mean to create 3 arrays
and fill them with random values
int n = 5;
int count_array = Convert.ToInt32(Console.ReadLine());
int[,] arr = new int[n, n];
Random rnd = new Random();
for (var i = 0; i < n; i++)
{
for (var j = i; j < n; j++)
{
---
}
}

Like that?
int n = 5;
int count_array = Convert.ToInt32(Console.ReadLine());
int[,,] arr = new int[count_array, n, n];
Random rnd = new Random();
for (int current_array = 0; current_array < count_array; current_array++)
{
Console.WriteLine($"Populating array #{current_array}:");
for (var i = 0; i < n; i++)
{
for (var j = 0; j < n; j++)
{
int value = rnd.Next();
arr[current_array, i, j] = value;
Console.Write(value+(j==n-1?"\r\n":","));
}
}
}
Console.ReadLine();

c# 2 Dimension Array Random Numbers

So I need to make 2 Dimension Array with random numbers, and expel the numbers like in multiplication table. It should look like this:
My code for now looks like this:
Random random = new Random();
int[,] array = new int[10, 10];
for (int i = 0; i < 10; i++)
{
for (int j = 0; j < 10; j++)
{
array[i, j] = random.Next();
Console.Write("\t{0}\t{1}" ,i,j);
}
EDIT:::This worked for me!
Random random = new Random();
int[,] array = new int[10, 10];
for (int i = 0; i < 10; i++)
{
for (int j = 0; j < 10; j++)
{
array[i, j] = random.Next(10);
Console.Write(array[i,j]+"\t");
}
Console.WriteLine("\n");

A 10x10 array of random numbers could be generated like this:
var rnd = new Random();
var randomArray = Enumerable.Range(0,10).Select(x => {
return Enumerable.Range(0,10).Select(y => rnd.Next()).ToArray();
}).ToArray();
Live example: http://rextester.com/GWTAK54347

As suggested by ThatBrianDude
static void Main(string[] args)
{
Random random = new Random();
int[,] array = new int[10, 10];
for (int i = 0;
i < 10;
i++)
{
for (int j = 0;
j < 10;
j++)
{
array[i,
j] = random.Next();
Console.Write("\t{0}",
array[i,
j]);
}
Console.Write("\n");
}
Console.ReadKey();
}

I think that this should work for you:
private static void RunArrayCode()
{
Random random = new Random();
int[,] array = new int[10, 10];
for (int i = 0; i < 10; i++)
{
for (int j = 0; j < 10; j++)
{
array[i, j] = random.Next();
// No tabs if it's the first item in a row
Console.Write("{0}{1}\t{2}", (j == 0 ? "" : "\t"), i, j);
}
// Each new row goes on its own line
Console.WriteLine();
}
}

how to remake 2d array random unique numbers as 3d?

static void Main(string[] args)
{
Random r = new Random();
int[,] x = new int[10,8];
int[] temp = new int[x.Length];
// two dimensional array and i want for three dimensional array
for(int i = 0; i < temp.Length; i++)
{
temp[i] = r.Next(10, 100);
for(int j = 0; j < i; j++)
{
if(temp[i] == temp[j])
{
i--;
break;
}
}
}
for(int i = 0, index = 0; i < x.GetLength(0); i++)
{
for(int j = 0; j < x.GetLength(1); j++)
{
x[i, j] = temp[index++]; //two dimensional array unique numbers
Console.Write(x[i, j] + " ");
}
}
// i want do it as for 3D and 4 D array unique numbers like that method what can i change or add?

It's pretty straight forward to do what you're doing for higher dimensions.
Here's my code for 3D:
var r = new Random();
int [,,] x = new int[10, 8, 8];
var count =
Enumerable
.Range(0, x.Rank)
.Select(y => x.GetLength(y))
.Aggregate((y, z) => y * z);
var values =
Enumerable
.Range(10, count)
.OrderBy(y => r.Next())
.ToArray();
var v = 0;
for (var i = x.GetLowerBound(0); i <= x.GetUpperBound(0); i++)
for (var j = x.GetLowerBound(1); j <= x.GetUpperBound(1); j++)
for (var k = x.GetLowerBound(2); k <= x.GetUpperBound(2); k++)
x[i, j, k] = values[v++];
To change it to 4D these lines change:
int [,,,] x = new int[10, 8, 8, 12];
// ...
var v = 0;
for (var i = x.GetLowerBound(0); i <= x.GetUpperBound(0); i++)
for (var j = x.GetLowerBound(1); j <= x.GetUpperBound(1); j++)
for (var k = x.GetLowerBound(2); k <= x.GetUpperBound(2); k++)
for (var l = x.GetLowerBound(3); l <= x.GetUpperBound(3); l++)
x[i, j, k, l] = values[v++];
Now, in this code I have explicitly called GetLowerBound as well as GetUpperBound as it is possible in .NET code to have a non-zero based array.
Also, rather than repeatedly re-try getting random numbers until you have unique numbers I simply generated a sequence of unique numbers and then randomly sorted them. That's a little different from your original code. You needed 80 (10 x 8) random values and you were choosing from values ranging from 10 to 99 inclusive. So you had some holes in your numbers.

Random r = new Random();
int[,,] x = new int[10, 8, 8];
int[] temp = new int[x.Length];
#region one dimensional array unique numbers.
for (int i = 0; i < temp.Length; i++)
{
temp[i] = r.Next(10, 650);
for (int j = 0; j < i; j++)
{
if (temp[i] == temp[j])
{
i--;
break;
}
}
}
#endregion
for (int i = 0, index = 0; i < x.GetLength(0); i++)
{
for (int j = 0; j < x.GetLength(1); j++)
{
for (int k = 0; k < x.GetLength(2); k++)
{
x[i, j, k] = temp[index++];
Console.Write(x[i, j, k] + " ");
}
Console.WriteLine();
}
}// i think it's correct code i've changed it

Genetic algorithm - clustering points on screen

Below is the code I wrote for clustering using genetic algorithm. Points are from a picturebox, generated randomly (X,Y) before calling this class. However, the result of this algorithm is much worse than k-means or lbg I'm comparing it to. Can someone take a look for any errors in the algorithm, maybe I omitted something. Thanks.
I did this using arrays, the 2 other I did using lists, but I don't think that should have any impact on result.
public class geneticAlgorithm
{
static int pom = 0;
static PictureBox pb1;
public geneticAlgorithm(PictureBox pb)
{
pb1 = pb;
}
public static void doGA(PointCollection points, int clusterCounter)
//points is a list of points,
//those point have (X,Y) coordinates generated randomly from pictureBox
//coordinates. clusterCounter is how many clusters I want to divide the points into
{
//this part converts list of points into array testtab,
//where each array field hold X,Y of a point
Point[] test = new Point[points.Count];
test = points.ToArray();
double[][] testtab = new double[test.Length][];
for (int i = 0; i < testtab.GetLength(0); i++)
{
testtab[i] = new double[2];
testtab[i][0] = test[i].X;
testtab[i][1] = test[i].Y;
}
//end of converting
int n = testtab.GetLength(0);
int k = clusterCounter;
int chromosomeCount = 500;
int dimensions = 2;
double[][] testClusters = new double[k][];
for (int i = 0; i < k; i++)
{
testClusters[i] = new double[dimensions];
}
double[][] testChromosomes = new double[chromosomeCount][];
for (int i = 0; i < chromosomeCount; i++)
{
testChromosomes[i] = new double[2 * k];
}
int[][] testChromosomesInt = new int[chromosomeCount][];
for (int i = 0; i < chromosomeCount; i++)
{
testChromosomesInt[i] = new int[2 * k];
}
double[] partner = new double[chromosomeCount];
double[][] roulette = new double[chromosomeCount][];
for (int i = 0; i < chromosomeCount; i++)
{
roulette[i] = new double[1];
}
double[][] errors = new double[chromosomeCount][];
for (int i = 0; i < chromosomeCount; i++)
{
errors[i] = new double[1];
}
double crossingPossibility = 0.01;
double mutationPossibility = 0.0001;
int maxIterations = 10000;
//here I create chromosomes and initial clusters
for (int j = 0; j < chromosomeCount; j++)
{
for (int i = 0; i < k; i++)
{
Random rnd = new Random();
int r = rnd.Next(n);
for (int q = 0; q < dimensions; q++)
{
testClusters[i][q] = testtab[r][q];
}
}
int help = 0;
for (int i = 0; i < k; i++)
for (int l = 0; l < dimensions; l++) // here is creation of chromosome
{
testChromosomes[j][help] = testClusters[i][l];
help++;
}
//end
//here I call accomodation function to see which of them are good
errors[j][0] = accomodationFunction(testClusters, testtab, n, k);
//end
//cleaning of the cluster table
testClusters = new double[k][];
for (int i = 0; i < k; i++)
{
testClusters[i] = new double[dimensions];
}
}
//end
for (int counter = 0; counter < maxIterations; counter++)
{
//start of the roulette
double s = 0.0;
for (int i = 0; i < chromosomeCount; i++)
s += errors[i][0];
for (int i = 0; i < chromosomeCount; i++)
errors[i][0] = chromosomeCount * errors[i][0] / s;
int idx = 0;
for (int i = 0; i < chromosomeCount; i++)
for (int j = 0; i < errors[i][0] && idx < chromosomeCount; j++)
{
roulette[idx++][0] = i;
}
double[][] newTab = new double[chromosomeCount][];
for (int i = 0; i < chromosomeCount; i++)
{
newTab[i] = new double[2 * k];
}
Random rnd = new Random();
for (int i = 0; i < chromosomeCount; i++)
{
int q = rnd.Next(chromosomeCount);
newTab[i] = testChromosomes[(int)roulette[q][0]];
}
testChromosomes = newTab;
//end of roulette
//start of crossing chromosomes
for (int i = 0; i < chromosomeCount; i++)
partner[i] = (rnd.NextDouble() < crossingPossibility + 1) ? rnd.Next(chromosomeCount) : -1;
for (int i = 0; i < chromosomeCount; i++)
if (partner[i] != -1)
testChromosomes[i] = crossing(testChromosomes[i], testChromosomes[(int)partner[i]], rnd.Next(2 * k), k);
//end of crossing
//converting double to int
for (int i = 0; i < chromosomeCount; i++)
for (int j = 0; j < 2 * k; j++)
testChromosomes[i][j] = (int)Math.Round(testChromosomes[i][j]);
//end of conversion
//start of mutation
for (int i = 0; i < chromosomeCount; i++)
if (rnd.NextDouble() < mutationPossibility + 1)
testChromosomesInt[i] = mutation(testChromosomesInt[i], rnd.Next(k * 2), rnd.Next(10));
//end of mutation
}
//painting of the found centre on the picture box
int centrum = max(errors, chromosomeCount);
Graphics g = pb1.CreateGraphics();
SolidBrush brush = new SolidBrush(Color.Red);
for (int i = 0; i < 2 * k - 1; i += 2)
{
g.FillRectangle(brush, testChromosomesInt[centrum][i], testChromosomesInt[centrum][i + 1], 20, 20);
}
return;
}
//end of painting
public static int max(double[][] tab, int chromosomeCount)
{
double max = 0;
int k = 0;
for (int i = 0; i < chromosomeCount; i++)
{
if (max < tab[i][0])
{
max = tab[i][0];
k = i;
}
}
return k;
}
public static int[] mutation(int[] tab, int elem, int bit)
{
int mask = 1;
mask <<= bit;
tab[elem] = tab[elem] ^ mask;
return tab;
}
public static double[] crossing(double[] tab, double[] tab2, int p, int k)
{
double[] hold = new double[2 * k];
for (int i = 0; i < p; i++)
hold[i] = tab[i];
for (int i = p; i < 2 * k; i++)
hold[i] = tab2[i];
return hold;
}
//accomodation function, checks to which centre which point belongs based on distance
private static double accomodationFunction(double[][] klastry, double[][] testtab, int n, int k)
{
double Error = 0;
for (int i = 0; i < n; i++)
{
double min = 0;
int ktory = 0;
for (int j = 0; j < k; j++)
{
double dist = distance(klastry[j], testtab[i]);
if (j == 0)
{
min = dist;
}
if (min > dist)
{
min = dist;
ktory = j;
}
}
Error += min;
}
pom++;
return 1 / Error;
}
public static double distance(double[] tab, double[] tab2)
{
double dist = 0.0;
for (int i = 0; i < tab.GetLength(0); i++)
dist += Math.Pow(tab[i] - tab2[i], 2);
return dist;
}
}
The algorithm should work like so: (excuse me if not the best english)
1. Get random points (let's say 100)
2. Check into how many clusters we want to split them (the same thing I would do using k-means for example
3. Get starting population of chromosomes
4. Throu cutting on the roulette, crossing and mutation pick the best x centres, where x is the amount of clusters we want
5. Paint them.
Here are some results, and why I think it's wrong: (it's using 100 points, 5 clusters)
k-means:
lbg:
genetic(without colors now):
I hope this clarifies a bit.

c# adding random numbers to array

I am making a array filled with random numbers in c# but I can't get it to work.
int[,] array = new int[10, 5];
int x, y;
x = 0;
y = 0;
while (y <= 5)
{
Random r = new Random();
int rand = r.Next(-50, 50);
array[x, y] = rand;
if (x == 10)
{
x = 0;
y++;
}
x++;
}

Use nested for loops, it is much easier:
Random rnd = new Random();
for (int i = 0; i < 10; i++)
{
for (int j = 0; j < 5; j++)
{
array[i, j] = rnd.Next(-50, 50);
}
}
Your while loop is not readable but it's correct,except you should change while (y <= 5) to while (y < 5) otherwise you will get an IndexOutOfRangeException. And you should define your Random instance outside of the loop.

int[,] array = new int[10, 5];
int x = 0, y = 0;
Random r = new Random();
while (y < 5)
{
int rand = r.Next(-50, 50);
array [x, y] = rand;
x++;
if (x == 10)
{
x = 0;
y++;
}
}

Try this:
int[,] array = new int[10, 5];
Random rnd = new Random();
for (int row = 0; row < 10; row++)
{
for (int col = 0; col < 5; col++)
{
array[row, col] = rnd.Next(-50, 50);
}
}

you need to change yours if or array declaration to
int[,] array = new int[11, 6];
also there is other problem, you need to create random before while
Random r = new Random();
while (y <= 5)
{
to print out the values you can use for
for (int i = 0; i < array.GetLength(0); i++)
{
for (int j = 0; j < array.GetLength(1); j++)
Console.WriteLine(array[i, j]);
}

int[,] array = new int[10, 5];
int x, y;
x = 0;
y = 0;
while (y < 5)
{
Random r = new Random();
int rand = r.Next(-50, 50);
array[x, y] = rand;
if (x == 9)
{
x = 0;
y++;
}
x++;
}
Let's see if this works.