how to count values in a matrix

I have a matrix with size 1887x2048, for each element is a number from 0 to 255. I want to find out how many elements is bigger than 100 and how many smaller than 100 (aka volume fraction)

Answer 1

[Walter Roberson]

 volumefraction = mean2(YourMatrix>100);

[Leon Phung]

oh wow, I'm trying to write a for loop that switching everything to 0 and 1 to solve this and you just nailed it with a single line, thank you very much.