PowerFactory offers intrinsic DSL 2-dimensional approximation functions: lapprox2 and sapprox2.

The attached project contains two DSL models for these two functions. The Common Models is stored inside the grid and the outputs are defined as:

y = lapprox2(xl,xc,matrix_a)

y = sapprox2(xl,xc,matrix_a)

The matrix (matrix_a) can be entered on the Common Model third page, page Advanced 2 - Two Dimensional Characteristics. The first line named Size defines the size of the matrix: The first cell contains the number of lines incl. the Axis line, the second cell contains the number of columns incl. the Axis column. The Axis line and the Axis column includes the axis values, i.e. defines xl1,xl2,xl3,.. and xc1,xc2,xc3. The remaining cells contain the y values.

There are additional functions for one dimensional look-up table: lapprox and sapprox. For more information refer to the User Manual.