I'm trying to demonstrate various array operations, and have a couple of questions. I'm having problems with printing out the column and row totals. It only prints out the totals of the last row and last column. It also only prints out the lowest of row 1 and the highest of row 3. I need it to give the row totals of each row, etc. Help?

public class ArrayOperations
{
public static void main (String [] args)
{
int [] [] numbers = {{1,2,3,4},
{5,6,7,8},
{9,10,11,12}};
int total;
int row = 0;
int col = 0;
int totalOfArray = getTotal(numbers);
int averageOfArray = getAverage(numbers);
int rowTotalOfArray = getRowTotal(numbers);
int columnTotalOfArray = getColumnTotal(numbers);
int rowHighest = getHighestInRow(numbers);
int rowLowest = getLowestInRow(numbers);


System.out.println("The sum of all the numbers in the array is:" + totalOfArray + ".");
System.out.println("The average of the numbers in the array is:" + averageOfArray + ".");
System.out.println("The sum of row " + row + " is " + rowTotalOfArray + ".");
System.out.println("The sum of column " + col + " is " + columnTotalOfArray + ".");
System.out.println("The lowest number of row " + row + " is " + rowLowest + ".");
System.out.println("The highest number of row " + row + " is " + rowHighest + ".");



}
public static int getTotal (int [] [] numbers)  //takes a two-dimensional array and returns the total of the values in the array.
{
int total = 0;      //Accumulator set to 0


//Sum the array elements.
for (int row = 0; row < numbers.length; row++)
{
for (int col = 0; col < numbers [row].length; col++)
total +=numbers[row][col];
}


return total;
}


public static int getAverage(int [] [] numbers) //takes two dimensional array and returns the average of the values.
{
int total = 0;      //Accumulator, set to 0


for (int row = 0; row < numbers.length; row++)
{
for (int col = 0; col<numbers [row].length; col++)
total +=numbers[row][col];
}


return total/numbers.length;
}


public static int getRowTotal (int [] [] numbers)
{
int total = 0;


for (int row = 0; row<numbers.length; row++)
{
//Set accumulator to 0.
total = 0;


//Sum a row.
for (int col = 0; col <numbers[row].length; col++)
total += numbers[row][col];
}
return total;


}


public static int getColumnTotal (int [] [] numbers)
{
int total = 0;      //Accumulator


for (int col = 0; col<numbers[0].length; col++)
{
//Set the accumulator to 0.
total = 0;


//Sum a column.
for (int row = 0; row < numbers.length; row++)
total += numbers[row][col];
}
return total;
}


public static int getLowestInRow (int [] [] numbers)
{
int low = numbers [0] [0];
for (int row = 1; row < numbers.length; row++)
{
for (int col =1; col<numbers[row].length; col++)
{
if (numbers[row][col] < low)
low = numbers[row][col];
}
}
return low;
}


public static int getHighestInRow (int [] [] numbers)
{
int high = numbers [0] [0];


for (int row = 1; row < numbers.length; row ++)
{
for (int col =1; col<numbers[row].length; col++)
{
if (numbers[row][col] > high)
high = numbers[row][col];
}
}
return high;
}



}

Edited 3 Years Ago by happygeek: fixed formatting

Sorry, here it is with the formatting.

public class ArrayOperations
{
	public static void main (String [] args)
	{
		int [] [] numbers = {{1,2,3,4},
							{5,6,7,8},
							{9,10,11,12}};
		int total;
		int row = 0;
		int col = 0;
		int totalOfArray = getTotal(numbers);
		int averageOfArray = getAverage(numbers);
		int rowTotalOfArray = getRowTotal(numbers);
		int columnTotalOfArray = getColumnTotal(numbers);
		int rowHighest = getHighestInRow(numbers);
		int rowLowest = getLowestInRow(numbers);
		
		System.out.println("The sum of all the numbers in the array is:" + totalOfArray + ".");
		System.out.println("The average of the numbers in the array is:" + averageOfArray + ".");
		System.out.println("The sum of row " + row + " is " + rowTotalOfArray + ".");
		System.out.println("The sum of column " + col + " is " + columnTotalOfArray + ".");
		System.out.println("The lowest number of row " + row + " is " + rowLowest + ".");
		System.out.println("The highest number of row " + row + " is " + rowHighest + ".");
		
	
	}
		public static int getTotal (int [] [] numbers)  //takes a two-dimensional array and returns the total of the values in the array.
		{
			int total = 0;		//Accumulator set to 0
			
			//Sum the array elements.
			for (int row = 0; row < numbers.length; row++)
			{
				for (int col = 0; col < numbers [row].length; col++)
					total +=numbers[row][col];
			}
			
			return total;
		}
		
		public static int getAverage(int [] [] numbers)	//takes two dimensional array and returns the average of the values.
		{
			int total = 0; 		//Accumulator, set to 0
			
			for (int row = 0; row < numbers.length; row++)
			{
				for (int col = 0; col<numbers [row].length; col++)
					total +=numbers[row][col];
			}
			
			return total/numbers.length;
		}
		
		public static int getRowTotal (int [] [] numbers)
		{
			int total = 0;
			
			for (int row = 0; row<numbers.length; row++)
			{
				//Set accumulator to 0.
				total = 0;
				
				//Sum a row.
				for (int col = 0; col <numbers[row].length; col++)
					total += numbers[row][col];
			}
			return total;
			
		}
		
		public static int getColumnTotal (int [] [] numbers)
		{
			int total = 0; 		//Accumulator
			
			for (int col = 0; col<numbers[0].length; col++)
			{
				//Set the accumulator to 0.
				total = 0;
				
				//Sum a column.
				for (int row = 0; row < numbers.length; row++)
					total += numbers[row][col];
			}
			return total;
		}
		
		public static int getLowestInRow (int [] [] numbers)
		{
			int low = numbers [0] [0];
			 for (int row = 1; row < numbers.length; row++)
			 {
			 	for (int col =1; col<numbers[row].length; col++)
			 	{
			 	if (numbers[row][col] < low)
			 		low = numbers[row][col];
			 	}
			 }
		  	return low;
		}
		
		public static int getHighestInRow (int [] [] numbers)
		{
			int high = numbers [0] [0];
			
			for (int row = 1; row < numbers.length; row ++)
			{
				for (int col =1; col<numbers[row].length; col++)
			 	{
			 	if (numbers[row][col] > high)
			 		high = numbers[row][col];
			 	}
			}
			return high;
		}
	
	
	}

You have this function returning an integer:

public static int getHighestInRow (int [] [] numbers)

and you have these lines that use the function:

int rowHighest = getHighestInRow(numbers);
System.out.println("The highest number of row " + row + " is " + rowHighest+".");

You initialize row as 0 and never change it, and you execute the above code exactly once. What is the display supposed to look like? If you want to display more than one integer, you need to either have getHighestInRow not return an integer or you need to call it more than once, perhaps in a for-loop. You are also not passing this function a single row. You are passing it all of the rows. Do you want to do that? Or do you want to do something like this:

for (row = 0; row < numbers.length; row++)
{
     // call getHighestInRow function for this row
     // display results of above function
}

If this is the case, you would need to change your array parameter:

public static int getHighestInRow (int [] [] numbers)

The existing function takes a 2-D array. A row is a single dimensional array.

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