To extend on CB's comment, you will find that the more effort you put into your post the better the resposes will be. Post up some code so we at least know what level you are at and how you are looking to approach the problem. The reason I think that this is so important is that we all have different ways of approaching the same problem. For example, I would not have generated a random list of numbers like CB did, I probably would have gone with a random indexing approach just because thats what I find simplest to picture:
Both methods will work, CB's method would probably lead to some tidier code in places but neither is right or wrong. There is no point of us posting up code that isn't going to be of any benefit to yourself.
rand_card_index = round(numel(deck)*rand())
rand_card = deck(rand_card_index)%get card
deck(rand_card) = %remove card