find index of value in array

hello, how can I find which numbers in a matrix are less than x and then print another number instead of the number I found?

Answer 1

[DGM]

A = randi(99,10,10) % test array

A = 10×10

11 29 88 59 64 59 20 49 53 65 60 75 47 68 47 69 2 43 13 46 37 70 50 17 82 37 64 72 86 75 33 13 2 76 57 66 74 76 10 99 53 9 79 5 62 83 8 46 94 83 47 58 88 62 79 36 5 56 57 53 88 4 19 64 49 53 22 25 98 90 18 79 23 97 34 47 41 42 38 53 51 93 3 94 78 45 32 5 39 14 44 16 58 26 77 94 8 89 50 34

x = 30;
lessthanx = A(A<x) % all the numbers in A that are < x

lessthanx = 25×1

11 18 29 13 9 4 16 2 19 23

fprintf('%d',randi(1000,1,1)) %  "print another number instead of the number I found"

463