interpolation with non-zero data only when using griddata

Hi

Happy New Year!

Could anyone here help me with below issue?

I am trying to show the contour of Well Injection Pressure on well trajectory. So I have well trajectory defined by coordinates of x and y using WellCoordinate(:,1),WellCoordinate(:,2), respectively. And I have also well injection pressure along well trajectory using WellInjPres. Now I am using griddata to plot contour of well injection pressure in xg,yg grid.

zg_wellinjpres=griddata(double(WellCoordinate(:,1)),double(WellCoordinate(:,2)),double(WellInjPres),double(xg),double(yg),'natural');

Now the result is: it also interpolates outside the well trajectory, please see picture. My question is how to remove the interpolation outside the well trajectory?

I like the interpolation is done only within well trajectory.

or could I just project data into the grid without interpolation?

Thank you so much for your help. I appreciate it.

Answer 1

[KSSV]

1. Get the boundary of your required region
2. use inpolygon to get the points lying inside and outside the boundary
3. Make the data for the points lying outside NaN.

[roudan]

Awesome KSSV, that is Perfect! It works!

Here are the codes it worked!

% find the boundary of well trajectories
k = boundary(WellCoordinate(:,1),WellCoordinate(:,2));
% check if point inside the grids of xg,yg inside the above well trajectory
% boundary lines
 inside_welltrajectory = inpolygon(xg,yg,WellCoordinate(k,1),WellCoordinate(k,2));
zg_wellinjpres(~inside_welltrajectory)=NaN;

I appreciate it, KSSV.