Linear interpolation between multiple points

Question

I have a set of points ( temperature, timestamp) I'm doing linear interpolation between those points and ramping. I would like to know how to use relative time instead of absolute time

deltaT = setPoint[y].time - setPoint[x].time; 

t = t + 1/deltaT; 

rOut = (1 - t) * setPoint[x].Temp + t * setPoint[y].temp;

Answer 1

First, find a timestamp corresponding to your "time zero". Let's say that we call it t0. We can define the relative times (denoted timeR here) by

setPoint[x].timeR = setPoint[x].time - t0;

Which we would compute for all of the points. From there, the computation looks pretty much the same:

deltaT = setPoint[y].timeR - setPoint[x].timeR; 

t = t + 1/deltaT; 

rOut = (1 - t) * setPoint[x].temp + t * setPoint[y].temp;