2. MODELING

CHAPTER 2 "MODELLING" 35 OBSERVATION: In the above way, only the grid is created. The mathematical model of the surface has not yet been created, which is done with the command in "Tools>> " Calculate ". The same dialog box, in addition to the Calculator, contains additional useful tools: • To change the colour of the grid, select it from the list and click the colour you want from the colour palette. • By using the buttons , , you can make the grid appear or not appear respectively. Select the grid you want to make visible or not visible and press the corresponding key. The indicator under the changes from (visible) to (not visible).