Topic: Writing code
Online Help
Numeric keypad
The numeric keypad is useful when you work on a tablet or laptop with touch screen. When you press a button, the respective symbols are inserted at the place of the cursor. The keypad is separated into four sections: "Numbers", "Operators", "Functions" and "Other". The "=" key does not calculate the answer as on simple calculators. This is the assignment operator (e.g. "a = 4"). If you need to check the equality of two numbers, use the "≡" operator (for example, "a ≡ b" means: "Is a equal to b?"). The "e", "π" and "g" keys insert the respective built-in constants e ≈ 2.7183, π ≈ 3.1416 and g ≈ 9.8066.
If you don't need the keypad and want to free some space, you can hide it with the 
button. Click again to show the keypad back.
The "C" button deletes the previous symbol and "AC" deletes a whole line. If you double click this button, you will clear the whole text. If you have done this accidentally, you can use Undo 
to restore.
Units. The "Units" tab, next to the "Keypad" tab, helps you insert units of measurement. The units are listed in three columns: unit system, category and units. Select a system and a category, then click a unit to insert it at the place of the cursor. Hover the mouse over a unit to see its description. If the units do not fit in the panel, they are arranged in columns that you can scroll with the mouse wheel. The tab contains the same units as the "Insert" → "Units" menu.