I'm a little hung up on "pattern of circles". Will it be single circles along a path, and they have random radii/width/size? Then I wouldn't think of it as a pattern. To me "pattern" usually implies....well, the opposite of "random".
So maybe you're describing your project in terms of Pattern Along Path?
If single circles, would the circle be aligned to the path at their centers? Or the top or bottom of the circles aligned along the path? (or inner or outer, in the case of a closed path).
If the path is going to be straight, tiled clones could be used. Or in any case, tiled clones could be used to create the random sized circles, and then you would do something else to align them to a path. Something like Moini described with making a group and use Scatter extension.
There are a couple of ways to use interpolate, as a way of creating the randomly sized circles. It's just arranging them in a random way
Mostly, I can't think of any way to do it all in one shot. There's some nagging little thought that there is a way to do it all at once. I just can't bring it into focus. But probably not. There are probably a few or even several ways to do it. But no matter which way, it will take a few or several steps.
I really hesitate to give a suggestion, without knowing more about it. How long of a path would it be? Would aligning the circles one at a time work? Or is it a very long path, or maybe multiple paths?
