Naming Objects

You can assign a certain name to an object when you create it using the Input Bar:

• Points: In GeoGebra, points are always named using upper case letters. Just type in the name (e. g., A, P) and an equal sign in front of the coordinates or commands.

Example: C = (2, 4), P = (1; 180°), Complex = 2 + i

• Vectors: In order to distinguish between points and vectors, vectors need to have a lower case name in GeoGebra. Again, type in the name (e. g., v, u) and an equal sign in front of the coordinates or commands.

Example: v = (1, 3), u = (3; 90°), complex = 1 – 2i

• Lines, circles, and conic sections: These objects can be named by typing in the name and a colon in front of their equations or commands.

Example: g: y = x + 3, c: (x-1)^2 + (y – 2)^2 = 4, hyp: x^2 – y^2 = 2

• Functions: You can name functions by typing, for example, f(x) = or g(x)= in front of the function’s equation or commands.

Example: h(x) = 2 x + 4, q(x) = x^2, trig(x) = sin(x)

Note:

• If you don’t manually assign a name to an object, GeoGebra assigns the names of new objects in alphabetical order.
• You can create indices within the names of objects by using an underscore. For example A₁ is entered as A_1 and s_AB is entered as s_{AB}.

Reserved labels

There are a few labels you can't use for objects: x, y, z, xAxis, yAxis, zAxis.

Once you create object dependent on imaginary unit i or Euler number e, auxiliary object called i (resp. e) is created. From that moment you cannot use this label for other objects. On the other hand, if you define for instance e=3, you will have to use special e character from the symbol list to get Euler number.

See also Labels and Captions.