Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.



Re: Interpolation of data
Posted:
Jul 18, 2014 10:30 AM


"inti" wrote in message <lqb2c7$f7e$1@newscl01ah.mathworks.com>... > Hi to all, > i set a period (T) of sending signal = 100ms, but when in my file log i saw that the difference between sending signal is varying , as example: (437 after 477 , the difference between these is < 100ms) For this reason, i interpolated it to get an estimated constant interval T by using interp1 function. > > The problem here that after applying interp1 , it gives me a 4320 row data OR my spreadsheet RES contains 392. > My program > > //if > s=data(:,3)+data(:,4)/1000; % convert to seconds+fractions > t = datenum(2014,07,18,data(:,1),data(:,2),s)*86400; > t = t  t(1); > sample = interp1(t,res(:,1:3), 0:0.01:t(end)); % i fixed a time to 100ms to obtain estimated data in this time > > > > // end > > > Is my program correct please? it is normal to obtain a rows sampled data > original data
Think about what you did.
What is the third argument you passed into interp1?
0:0.01:t(end)
What is t(1)? Why would you start interpolating at 0? What do you expect it to do?
John



