Checking a 1x24 Array for numbers less than 0

I need assistance with changing a number less than 0 in an array to 0. I attempted to program this but I am lost. Any help would be appreciated.

Answer 1

[Changoleon]

for example if a is the matrix

a = [ 0 2 1 -9 -8 6 100 -63 1 2 5];

you can do following

a(a<0)=0;

Now a has just the values equal or greater than zero