Hi,I have numerical matrix 4X4, I have to classify numbers in grades like less than 20, greater than 20 and less than 20, so Hhow can I do it?

I have numerical matrix 4X4, I have to classify numbers in grades like less than 20, greater than 20 and less than 20, so how can I do it?

Answer 1

[Thorsten]

X = randi(30, [4 4])
g20 = X(X > 20)
le20 = X(X <=20)

[Anup Badve]

Thank you Thorsten !

Answer 2

[Jack Breenlair]

You want to use two for loops that go through the matrix checking if the numbers satisfy the conditions that you require.

auxiliar=0;

for i=1:4
    for j=1:4
      if A(i,j)==condition
      auxiliar=auxiliar+1;
      end

      end
  end

something like this

[Guillaume]

The code above can be reduced simply to:

auxiliar = nnz(A == condition);

No need for loops.

[Anup Badve]

Thank you Guillaume !

[Anup Badve]

Thank you Jack !