How to make a certain percentage of values in an existing matrix, between a set range of values. Probably easy but I am a newbie.

size=[25,10];

Score=randi([50,100],size);

So I have these commands in my script to create a 25x10 matrix of randomly assigned values between 50 and 100. However I need to make 10% of those randomly assigned values between 30 and 50, with the ability to change the percentage at will. Any help would be great.

Answer 1

[Rub Ron]

What about this:

size=[25,10];                 
Score=randi([50,100],size);

my_percentage = 10; 

my_piece = prod(size)*my_percentage/100;
sub_score=randi([30,50],[1, my_piece]);
rand_idx = randperm(prod(size),my_piece);

Score(rand_idx)=sub_score;