javascript - what are the different parameters in jQuery's easing functions -

i see jquery's easing functions @ https://github.com/danro/jquery-easing/blob/master/jquery.easing.js.

i see each function takes 5 paramaters can't figure out of them , how tie call animate.

• x - ????
• t - current time - new date()???
• b - beginning value
• c - change in value ???
• d - duration

for example, call function like:

$("div").width(50).animate({     width: 150px }, 2000); 

would call match so:

• x - ????
• t - current time @ each call update
• b - 50px
• c - 100px
• d - 2000

x parameter not needed equations, necessary compatibility jquery

reference : link

so x equal null , t expressed in milliseconds since start of animation

i think have right others.

you can see this post more comprehension