Thread: 2d Arrays

I have to create a lab that will
Print out the input 2D-array as an image on the console screen.
• Replace 0 by “ ” {space}.
• Replace values between 1 and 99 by “.” {one dot}.
• Replace values between 100 and 199 by “..” {two dots}.
• Replace values between 200 and 254 by “…” {three dots}.
• Replace 255’s by “x”.
- Remember to check if the dimensions of input array are valid numbers.
- Make use of method printf properly to print out the image nicely.

2.
- Change all numbers n in the array by (255-n).
- Print out the new matrix as well as the new image (using method Display).
- Remember to check if the dimensions of input array are valid numbers.

3.- Look for the pattern array inside the image.
- Erase the places where the pattern is found, i.e., change them to black (0).
- Print the 2D-array: before, and after if the pattern has been found.
- Return 1 if pattern is found, 0 otherwise.
- Example:
Image ( Before )

0 0 0 0 0
0 234 123 0 0
78 56 34 234 34
187 0 26 190 0
0 190 36 0 23
Pattern

0 234 123 0
78 56 34 234


Image ( After )

0 0 0 0 0
0 0 0 0 0
0 0 0 0 34
187 0 26 190 0
0 190 36 0 23

public class Lab7
{
public static void Display(int[][] image)
	{
		for(int i = 0; i < image.length; i++) //rows
		{
			for(int j = 0; j < image[0].length; j++) //columns
			{
				if(image[i][j] == 0)
					System.out.print("   ");
				else if(image[i][j] >= 1 && image[i][j] <= 99)
					System.out.print(" . ");
				else if(image[i][j] >= 100 && image[i][j] <= 199)
					System.out.print(" .. ");
				else if(image[i][j] >= 200 && image[i][j] <= 254)
					System.out.print(" ... ");
				else 
					System.out.print(" x ");
			}
			System.out.println();
		}
	}//end method
                     public static void Modify(int[][] image)
	{
		int[][] modImage = new int[10][10];
		int n;
 
		for(int i = 0; i < image.length; i++) //rows
		{
			for(int j = 0; j < image[0].length; j++) //columns
			{
				n = (255 - image[i][j]);
 
				modImage [i][j]= n;
			}
		}
		Display(modImage);
	}//end method
	public static int extractFeature(int[][] image, int[][] pattern)
	{
		int[][] extractImage = new int[10][10];
		int found = 0;
 
		return found;
 
	}//end method

I am Having Problems putting together the method extract feature if anyone can guide me in the right direction to have a working method? that is the only one that I need help with.

I worked on the code and I came up with this but when I run it it does not run properly because it stops checking for the other numbers once it finds the first ones.

	public static int extractFeature(int[][] image, int[][] pattern)
	{
		int[][] extractImage = new int[10][10];
		int found = 0;
 
		if (pattern.length <= image.length && pattern[0].length <= image[0].length){
			for (int i = 0; i < pattern.length; i++)
				{
				for( int j = 0; j < pattern[0].length; j++)
				{
					for (int pcol = 0; pcol < pattern.length; pcol++)
					{
						(int prow = 0; prow < pattern[0].length; prow++)
						{
							if ( image[i][j] != pattern[prow][pcol]){
								break;
							}else if ((prow == pattern.length - 1) && (pcol == pattern[0].length - 1))
								{
									found = 1;
									return found;
								}
							}
						}	
					}
				}
 
		return found;
		}
 
	}//end method

I added in the for where I was missing it in my loop, but the code is still not working. it only returns 1 to me once it finds the first part of the pattern it doesnt check the pattern completely.

Yeah but I want it to return 1 only if the pattern is found inside my array else it should return 0, my code keeps returning 1 if the first digit in the pattern is found which I dont want it to do, I only want one if the whole pattern is inside the array. I dont know how to scan the whole array for the pattern so that it could return 1 if the pattern is found and 0 if the whole pattern is not found.