# What is the solution for "Error using griddedInterpolant The grid vectors must contain unique points."

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arifahazwani AY on 8 Sep 2020
Commented: arifahazwani AY on 8 Sep 2020
Hi,
I need to interpolate the data of 243 frame into 51 frame which 0 to 100%. However, the result shows
"Error using griddedInterpolant The grid vectors must contain unique points."
I'm not sure how to solve the error and what is the meaning of unique points.
% Make original data
oldPcntValsx = X(:,1) ;
oldXvals = X(:,2) ;
% Set a new spacing from 0 to 1 and interpolate
newPcntValsx = 0:2:100;
newXvals = interp1(oldPcntValsx, oldXvals, newPcntValsx);
newX = newXvals(:);
% Make original data
oldPcntValsy = X(:,1) ;
oldYvals = X(:,3) ;
% Set a new spacing from 0 to 1 and interpolate
newPcntValsy = 0:2:100;
newYvals = interp1(oldPcntValsy, oldYvals, newPcntValsy);
newY =newYvals(:);
% Make original data
oldPcntValsz = X(:,1) ;
oldZvals = X(:,4) ;
% Set a new spacing from 0 to 1 and interpolate
newPcntValsz = 0:2:100;
newZvals = interp1(oldPcntValsz, oldZvals, newPcntValsz);
newZ = newZvals(:);
N2 = [newX,newY,newZ];

Dana on 8 Sep 2020
You're interpolating based on the gridpoints located in column J of your Excel file. Each gridpoint must be unique (i.e., different from every other gridpoint), but J188 = J189. That's why you're getting an error.

#### 1 Comment

arifahazwani AY on 8 Sep 2020
Its workk.! I had go through the data several times but mislook that error.
Thank you very much!!