Question

MATLAB, if-else

Write a script which to do the following. Take an array of any size as input and check if all the elements are integers. (i) If not, display the error message ‘Invalid input!’. Use the error command to create a proper error message in red. (ii) If yes, count the number of rows where the sum of the elements is smaller than the average row sum. It is recommended that you use a test variable with many rows (> 10 ).

Answer 1

Case 1 :

When the matrix contains elements that are not integers

MATLAB code :

A = rand(11,11)
[rows,columns] = size(A);
row_sum = sum(A,2);
total = sum(row_sum);
avg_row_sum = total / rows;

count = 0;
for i = 1:rows
    sum = 0;
    for j = 1:columns
        if floor(A(i,j)) ~= A(i,j)
            error('Invalid Input')
            return
        else
            sum = sum + A(i,j);
        end
    end
    if sum < avg_row_sum
        count = count + 1;
    end
end
disp(['The number of rows with sum smaller than average is : ', num2str(count)])

Output :

.

Case 2 :

When the matrix contains elements that are integers

MATLAB code :

A = randi([1,10],[11,11])
[rows,columns] = size(A);
row_sum = sum(A,2);
total = sum(row_sum);
avg_row_sum = total / rows;

count = 0;
for i = 1:rows
    sum = 0;
    for j = 1:columns
        if floor(A(i,j)) ~= A(i,j)
            error('Invalid Input')
            return
        else
            sum = sum + A(i,j);
        end
    end
    if sum < avg_row_sum
        count = count + 1;
    end
end
disp(['The number of rows with sum smaller than average is : ', num2str(count)])

Output :

.

.