What is correct method to change DMP default parameters

[xlla]

I have run example MPU6050_DMP6.ino with teapot visualizer, it works perfectly.

Now I want to change some default parameters, like sample rate and FIFO rate.
@jrowberg was said we can direct change MPU6050_DMP_FIFO_RATE_DIVISOR, as comment said, it control FIFO rate, but how actually sample rate ?

I have trace down method dmpInitialize(), and find function setRate(), it's comment said that FIFO output, DMP sampling, etc all base on sample rate, so I should call this function with desired parameter too ?

if so , should I modify code in function dmpInitialize directly or invoke those settings function after call dmpInitialize and before call setDMPEnabled?

[xlla]

after read this post, about raw rate and dmp rate

I still confused how or when to change those parameters.
I see func dmpInitialize transfer some binary data then change those parameters then transfer another binary data , and then resetDMP() .
if I want to change some parameters should I among those binary data transfer?
and should I call resetDMP() after change those paramters?