diff --git a/appj.adoc b/appj.adoc index 3b7539f7..8b855c99 100644 --- a/appj.adoc +++ b/appj.adoc @@ -17,6 +17,7 @@ The appendix is organised in a sections on <>, The coordinate interpolation methods are named to indicate the number of dimensions they interpolate as well as the type of interpolation provided. For example, the interpolation method named `linear` provides linear interpolation in one dimension and the method named `bi_linear` provides linear interpolation in two dimensions. Equivalently, the interpolation method named `quadratic` provides quadratic interpolation in one dimension and the interpolation method named `bi_quadratic` provides quadratic interpolation in two dimensions. When an interpolation method is referred to as linear or quadratic, it means that the method is linear or quadratic in the indices of the interpolated dimensions. +Consequently, for a linear interpolation, the coordinates of the interpolated points are evenly spaced. For convenience, an interpolation argument `s` is introduced, calculated as a function of the index in the target domain of the coordinate value to be reconstituted. In the case of one dimensional interpolation the variable is computed as