Integration and Differentiation

[koolguy]

Can we use this Integration and Differentiation in micro ??

 

[KeepItSimpleStupid]

the term is "numerical methods" Both integration and differentiation are done all the time when implementing a PID algorithm.

 

[koolguy]

how it is done?

 

[MrAl]

Hi,

Basic integration in time is done by accumulating the input times the time increment.
So if you take samples every 0.1 second you have a time increment of 0.1 second so you multiply each sample by 0.1 and add that to the previous result:
sum=sum+dt*v[k]
where
dt is the time increment,
v[k] is the sample measurement at that time.

The basic first derivative in time can be calculated by taking the difference of two successive samples and divided by the time increment:
dv/dt[k]=(v[k+1]-v[k])/dt

and a slightly better way is to take samples at k-1 and at k+1:
dv/dt[k]=(v[k+1]-v[k-1])/(dt+dt)

where you might note that we get the derivative for the sample k by using samples k-1 and k+1 rather than sample k itself. It's sometimes referred to as the "Central Means" derivative.

There are a lot of different numerical methods for different things so you might look into this more on the web or ask more questions here