Difference between revisions of "Boolean values"
From GeoGebra Manual
(== and != for numbers, points, lines, conics, functions (needs CAS), planes, a, b) |
(added interlink and example of use) |
||
| Line 1: | Line 1: | ||
<noinclude>{{Manual Page|version=5.0}}</noinclude>{{objects|general}} | <noinclude>{{Manual Page|version=5.0}}</noinclude>{{objects|general}} | ||
You can use the Boolean variables ''true'' and ''false'' in GeoGebra. Just type, for example, | You can use the Boolean variables ''true'' and ''false'' in GeoGebra. Just type, for example, | ||
| − | <code>a = true</code> or <code>b = false</code> into the [[Input Bar]] and press the Enter | + | <code>a = true</code> or <code>b = false</code> into the [[Input Bar]] and press the {{KeyCode|Enter}} key. |
| + | With Boolean variables you can e.g. define the [[Conditional Visibility|conditional visibility]] of an object. | ||
==Check Box and Arrow Keys== | ==Check Box and Arrow Keys== | ||
Revision as of 12:06, 18 August 2022
You can use the Boolean variables true and false in GeoGebra. Just type, for example,
a = true or b = false into the Input Bar and press the Enter key.
With Boolean variables you can e.g. define the conditional visibility of an object.
Check Box and Arrow Keys
Free Boolean variables can be displayed as check boxes in the 
Graphics View (see tool
Check Box Tool). After selecting a Boolean variable in the 
Algebra View you can use the arrow keys to change the value of the Boolean variable (see Manual Animation).
Note: You may also use Boolean variables like numbers (value 0 or 1). This allows you to use a checkbox as the dynamic speed of an animated slider allowing you to start and stop the animation. In this case, the animation button is only shown in the Graphics View if there is also an animated slider with static (i.e. non-dynamic) speed.
Graphics View if there is also an animated slider with static (i.e. non-dynamic) speed.Operations
You can use the following operations for Boolean variables and conditions in GeoGebra by either selecting them from the list next to the Input Bar or by entering them using the keyboard:
| Operation | List | Keyboard | Example | Object types |
|---|---|---|---|---|
| Equal | ≟ | == | a ≟ b or a == b | numbers, points, lines, conics, functions (needs CAS), planes, a, b |
| Unequal | ≠ | != | a ≠ b or a != b | numbers, points, lines, conics, functions (needs CAS), planes a, b |
| Less than | < | a < b | numbers a, b | |
| Greater than | > | a > b | numbers a, b | |
| Less or equal than | ≤ | <= | a ≤ b or a <= b | numbers a, b |
| Greater or equal than | ≥ | >= | a ≥ b or a >= b | numbers a, b |
| And | ∧ | && | a ∧ b or a && b | Booleans a, b |
| Or | ∨ | || | a ∨ b or a || b | Booleans a, b |
| Not | ¬ | ! | ¬a or !a | Boolean a |
| Parallel | ∥ | a ∥ b | lines a, b | |
| Perpendicular | ⊥ | a ⊥ b | lines a, b | |
| Belongs to | ∈ | a ∈ list1 | number a, list of numbers list1 |
