Difference between revisions of "Naming Objects"
From GeoGebra Manual
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* [[Points and Vectors|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. | * [[Points and Vectors|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|1=<code>v = (1, 3)</code>, <code> u = (3; 90°)</code>}} | {{example|1=<code>v = (1, 3)</code>, <code> u = (3; 90°)</code>}} | ||
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* [[Lines and Axes|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. | * [[Lines and Axes|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|1=<code>g: y = x + 3</code>, <code>c: (x-1)^2 + (y – 2)^2 = 4</code>, <code>hyp: x^2 – y^2 = 2</code>}} | {{example|1=<code>g: y = x + 3</code>, <code>c: (x-1)^2 + (y – 2)^2 = 4</code>, <code>hyp: x^2 – y^2 = 2</code>}} |
Revision as of 13:55, 26 July 2011
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°)
- 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°)
- 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) =
org(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 sAB is entered ass_{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.