Hello all,

I can't get my stupid head around CDF (Cumulative distribution function). How do you form a single expression (if that's the right word) for F(x) if you have it like this (for example):

$\displaystyle F(x) = 0 \ for \ x < 0$

$\displaystyle F(x) = 1/6 \ for \ 0 < x < 1$

$\displaystyle F(x) = 5/6 \ for \ 1 < x < 2$

$\displaystyle F(x) = 1 \ for \ x > 2$

So what I want to be able to do is write the above as something I can integrate/differentiate or whatever, presuming it's possible. The book I'm using just says "so we write the above as F(x) = blah blah blah" without a single explanation of how to do it. So what I'd like to know is... how do you do it?

(P.s. I'm not too concerned with the answer to the above question, I'm just studying...so whatever examples you want to use are fine).

Thanks.