Chapters: 1: Introduction 2: Simple example 3: Invocation 4: Finer Control 5: X-Y Plots 6: Contour Plots 7: Image Plots 8: Examples 9: Gri Commands 10: Programming 11: Environment 12: Emacs Mode 13: History 14: Installation 15: Gri Bugs 16: Test Suite 17: Gri in Press 18: Acknowledgments 19: License Indices: Concepts Commands Variables | ### 9.3.21: ``interpolate`'
    interpolate x grid to .left. .right. .inc.|{/.cols.}'
    interpolate y grid to .bottom. .top. .inc.|{/.rows.}'
Transform grid by interpolating between existing grid data, according to a new x or y grid specified in the manner of ``set x grid`' and ``set y grid`'. Note that the new grid is neccessarily regular, while the first grid needn't have been. The data of the new grid are constructed by interpolation, using the same interpolation algorithm as the ``convert grid to image`' command.