# Difference between revisions of "Naming Objects"

From GeoGebra Manual

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==Reserved labels== | ==Reserved labels== | ||

− | + | These are the labels you can't use for objects: x, y, xAxis, yAxis, zAxis, abs, | |

+ | sgn, sqrt, exp, log, ln, ld, lg, cos, sin, tan, | ||

+ | acos, arcos, arccos, asin, arcsin, atan, arctan, | ||

+ | cosh, sinh, tanh, acosh, arcosh, arccosh, asinh, | ||

+ | arcsinh, atanh, arctanh, atan2, erf, | ||

+ | floor, ceil, round, random, conjugate, arg, | ||

+ | gamma, gammaRegularized, beta, betaRegularized, | ||

+ | sec, csc, cosec, cot, sech, csch, coth | ||

In the symbol list of the input bar, you will find special characters for the following constants: | In the symbol list of the input bar, you will find special characters for the following constants: | ||

− | * π - the circle constant pi | + | * π - the circle constant pi, which you can also type with <Alt>p |

− | * ℯ - the Euler number, e.g. for the exponential function ℯ^x | + | * ℯ - the Euler number, e.g. for the exponential function ℯ^x, which you can also type with <Alt>e |

− | * ί - the imaginary unit, e.g. for complex numbers like z = 3 + ί | + | * ί - the imaginary unit, e.g. for complex numbers like z = 3 + ί, which you can also type with <Alt>i |

− | When the variable names e | + | When the variable names e and i are not used yet, they are automatically read as ℯ and ί respectively for convenience. |

See also [[Labels and Captions]]. | See also [[Labels and Captions]]. |

## Revision as of 23:13, 13 September 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) =`

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 A
_{1}is entered as`A_1`

and s_{AB}is entered as`s_{AB}`

.

## Reserved labels

These are the labels you can't use for objects: x, y, xAxis, yAxis, zAxis, abs, sgn, sqrt, exp, log, ln, ld, lg, cos, sin, tan, acos, arcos, arccos, asin, arcsin, atan, arctan, cosh, sinh, tanh, acosh, arcosh, arccosh, asinh, arcsinh, atanh, arctanh, atan2, erf, floor, ceil, round, random, conjugate, arg, gamma, gammaRegularized, beta, betaRegularized, sec, csc, cosec, cot, sech, csch, coth

In the symbol list of the input bar, you will find special characters for the following constants:

- π - the circle constant pi, which you can also type with <Alt>p
- ℯ - the Euler number, e.g. for the exponential function ℯ^x, which you can also type with <Alt>e
- ί - the imaginary unit, e.g. for complex numbers like z = 3 + ί, which you can also type with <Alt>i

When the variable names e and i are not used yet, they are automatically read as ℯ and ί respectively for convenience.

See also Labels and Captions.