Clicking a cell and pressing the = key opens the Formula Editor. By default this appears as a narrow single line, but can be stretched both horizontally and vertically. Making the Formula Editor larger helps you input and analyse larger formulae.
In the example an IF query has been used. The formula used was typed like this:
IF(F2= “Red”, 10,
The cell F2 is selected in the screen shoot, rather than being labelled F2 in the Formula Editor the name is created from its headers Colour and Curtain 1, but the cell referenced is F2.
In plain English the formula reads if the cell F2 contains the word Red, then return a value of 10. Referring to the curtain designer example this could be used to turn a fabric colour into a money value say £10 per metre if red, or £8 if green.
It would be import to use pop-up menus for the colours, fabrics and so on as mistyping red, green, or blue in this equation would return an error.
When the Formula Editor is open the inspector changes to a Function browser that list functions grouped in to disciplines such as Engineering, Financial, and Statistical. The browser also gives examples of the functions in a variety of formulae to help explain their use.