linear interpolation of angular data over a grid

I have scattered data of certain angles ranging from 0 to pi that I want to interpolate on a grid. For my purposes 0 and pi are "pointing" in the same direction, but my problem is the same as with 0 to 2pi. I'm using griddata and linear interpolation won't suite my purpose as it will turn areas between 0 and pi into pi/2 not recognizing that 0 and pi are pointing the same way. I can't collapse my data into an interval of 0-pi/2 as the pi/4 points and 3pi/4 points shouldn't be treated the same.

Answer 1

[Abel Abraham]

Found a function on file exchange!

https://www.mathworks.com/matlabcentral/fileexchange/8720-interp2pi?s_tid=srchtitle_angle%20data%20interpolation_1

This works from 0-360 degrees, so I can just multiply my 0-pi values by 2 and convert to degrees.