JQuery :: How To Re-use Function For Change Event

I know in JavaScript you are able to write functions that you can just call at a later time. I'm working on a jQuery UI slider, and I wrote a function for the animation that happens when you start sliding. I would also like this same function to fire for the "change" event, but I can't seem to get it to work.

Here is the shortened code sample:
$(function(){
var posterO = $(".poster-slider")
.slider({
slide: function(event, ui){
//This is the function I would like to reuse at "change", below
poster.css(...);
posterLi.css( ... );
ptCopy.css( ... );
sliderValue = ui.value;
},
//change:,
animate:true
});
//When "#abundant-trees" link is clicked, the slider handle changes, firing the "change" event, but the "slide" function is not called.
$("#poster-switcher a[href=#abundant-trees]").click(function(link){
posterO.slider("value", 100);
link.preventDefault(); //Stop browser from following the link that was clicked on.
})});
I would like to apply the "slide" function to the "change" event without having to duplicate all the code.