How to plot a smooth curve with eliminating NAN and complex datapoint?

close all clear clc Y=xlsread('PET'); Y1=Y(:,1); Xp=cumtrapz(Y(:,2)); Xp1=trapz(Y(:,2)); X=Xp/Xp1; W=log(X); W1=log(W); T=log(Y1); n=polyfit(T,W1,1); Z=W/(Y1^n);

[Syed Muhammad Hassan Mehdi]

Above is the code I want to find value of n and Z but my data points are undefined in W. Removing the undefined data points. My datapoint are unequally spaced. Any help will be highly regarded. Have been stuck on this since two days Thanks in advance