Interpolation Function
What you can do is use interp1 function. This function will fit in deifferent way the numbers for a new X series.
For example if you have 
x=[1 3 5 6 10 12] 
y=[15 20 17 33 56 89]
This means if you want to fill in for x1=[1 2 3 4 5 6 7 ... 12], you will type 
y1=interp1(x,y,x1)
This is probably a very easy question, but all the sources I have found on interpolation in Matlab are trying to correlate two values, all I wanted to benefit from is if I have data which is collected over an 8 hour period, but the time between data points is varying, how do I adjust it such that the time periods are equal and the data remains consistent?
Or to rephrase from the approach I have been trying: I have GPS lat,lon and Unix time for these points; what I want to do is take the lat and lon at time 1 and time 3 and for the case where I don't know time 2, simply fill it with data from time 1 - is there a functional way to do this? (I know in something like Python Pandas you can use fill) but I'm unsure of how to do this in Matlab.