Variables

Introduction

The Variables blocks in VEXcode 123 allow for storing and managing data, including numbers, Boolean values, lists, and 2D lists.

To make a variables blocks appear you must first create a variable. Variables are created using the Make buttons in the Variables category. All variables are global by default, meaning they can be used anywhere in the project.

Below is a list of available blocks:

Numeric Variables - Store and modify numbers.

• numeric variable – Returns the value of a numeric variable.

• set numeric variable – Assigns a value to a numeric variable.

• change numeric variable – Increases or decreases a numeric variable by a set amount.

Boolean Variables – Store True or False values.

• Boolean variable – Returns the value of a Boolean variable.

• set Boolean variable – Assigns a True or False value to a Boolean variable.

Lists – Store and manage collections of values.

• list item – Returns a value from a list based on its position.

• replace list item – Updates a specific item in a list.

• set list items – Assigns values to a list.

• length of list – Returns the number of items in a list.

2D Lists – Store and manage collection of values in a grid.

• 2D list item – Returns a value from a specific row and column in a 2D list.

• replace 2D list item – Updates a specific item in a 2D list.

• set 2D list items – Assigns values to a 2D list.

• length of 2D list – Returns the number of rows or columns in a 2D list.

numeric variable

The numeric variable reporter block is used to return the numeric value assigned to the variable.

The Numeric variable reporter block.

(myVariable)

Parameter	Description
	This block has no parameters.

Example

cuando empezó
[Display the value of the variable plus two.]
establecer de [my_variable v] a [2]
imprimir ((my_variable) [math_plus v] [2]) ▶

set numeric variable

The set numeric variable block assigns a value to a numeric variable.

The set Numeric variable reporter block.

establecer de [myVariable v] a [1]

Parameter	Description
variable	The numeric variable to assign a value to. Users can select an existing variable, rename it, or delete it.
value	The number assigned to the variable (can be a whole number, decimal, or numeric block).

Example

cuando empezó
[Set a variable to 10 and display it.]
establecer de [my_variable v] a [10]
imprimir (my_variable) ▶

change numeric variable

The change numeric variable block increases or decreases a variable’s value by a given amount.

The Change Numeric Variable stack block.

cambiar [myVariable v] por (1)

Parameter	Description
variable	The numeric variable to modify. Users can select an existing variable, rename it, or delete it.
value	The amount to increase or decrease the variable by.

Example

cuando empezó
[Increase the variable by 5 and display it.]
establecer de [my_variable v] a [10]
cambiar [my_variable v] por [5]
imprimir (my_variable) ▶

Boolean variable

The Boolean variable block is used to return either a True or False value.

The Boolean Variable reporter block.

<myBoolean>

Parameter	Description
	This block has no parameters.

Example

cuando empezó
[Display a message if the variable is set to True.]
establecer de [my_boolean v] a <true v>
si <my_boolean> entonces
imprimir [Boolean is True!] ▶
fin

set Boolean variable

The set Boolean variable block assigns a True or False value to a Boolean variable.

The Set Boolean Variable stack block.

establecer de [myBoolean v] a <true v>

Parameter	Description
variable	The Boolean variable to assign a value to. Users can select an existing variable, rename it, or delete it.
value	A Boolean value (True or False).

Example

cuando empezó
[Display different messages based on the Boolean value.]
establecer de [my_boolean v] a <true v>
si <my_boolean> entonces
imprimir [It's true!] ▶
demás
imprimir [That's false...] ▶
fin

list item

The list item block is used to return the value of an item in a list.

The List Item reporter block.

(artículo (1) de [myList v])

Parameter	Description
index	The position of the item in the list (starting at 1).
variable	The list variable to return an item from. Users can select an existing list, rename it, or delete it.

Example

cuando empezó
[Display the second item from a list.]
establecer [my_list v] a [Red] [Green] [Blue]
imprimir (artículo (2) de [my_list v]) ▶

replace list item

The replace list item block updates a specific item in a list.

The Replace List Item stack block.

reemplazar el elemento (1) de [myList v] a (1)

Parameter	Description
variable	The list variable containing the item to modify. Users can select an existing list, rename it, or delete it.
index	The position of the item in the list (starting at 1).
value	The new value assigned to the specified list item.

Example

cuando empezó
[Replace the first item in a list with "Robot".]
establecer [my_list v] a [Red] [Green] [Blue]
reemplazar el elemento (1) de [my_list v] a [Robot]
imprimir (artículo (1) de [my_list v]) ▶

set list items

The set list items block sets every item in the list to the entered values.

The Set List Items stack block.

establecer [myList v] a (0) (0) (0)

Parameter	Description
variable	The list variable being assigned values. Users can select an existing list, rename it, or delete it.
values	The values to store in the list, entered as individual items.

Example

cuando empezó
[Display the last item in a list.]
establecer [my_list v] a [Red] [Green] [Blue]
imprimir (artículo (3) de [my_list v]) ▶

length of list

The length of list block returns the number of items in a list.

The Length of List reporter block.

(longitud de [myList v])

Parameter	Description
variable	The list variable to return the length of. Users can select an existing list, rename it, or delete it.

Example

cuando empezó
[Display how many items are in a list.]
establecer [my_list v] a [Red] [Green] [Blue]
imprimir (longitud de [my_list v]) ▶

2D list item

The 2D list item block is used to return the value of an item in a 2D list.

The 2D List Item reporter block.

(artículo (1) (1) de [my2DList v])

Parameter	Description
row	The row of the item (starting at 1).
column	The column of the item (starting at 1).
variable	The 2D list variable to return an item from. Users can select an existing 2D list, rename it, or delete it.

Example

cuando empezó
[Display an item from a 2D list.]
establecer [my_2d_list v] a ([1][Red]) ([2] [Green])
imprimir (artículo (2) (2) de [my_2d_list v]) ▶

replace 2D list item

The replace 2D list item block updates a specific item in a 2D list.

The Replace 2D List Item stack block.

reemplazar elemento (1) (1) de [my2DList v] a (1)

Parameter	Description
row	The row index of the item (starting at 1).
column	The column index of the item (starting at 1).
variable	The 2D list variable containing the item to modify. Users can select an existing 2D list, rename it, or delete it from the drop-down menu.
value	The new value assigned to the specified 2D list item.

Example

cuando empezó
[Replace a value in a 2D list and print the updated item.]
establecer [my_2d_list v] a ([1][Red]) ([2] [Green])
reemplazar elemento [2] [2] de [my_2d_list v] a [Blue]
imprimir (artículo (2) (2) de [my_2d_list v]) ▶

set 2D list items

The set 2D list items block sets every item in the 2D list to the entered values.

The Replace 2D List Item stack block.

establecer [my2DList v] a ([0][0]) ([0][0])

Parameter	Description
variable	The 2D list variable being assigned values. Users can select an existing 2D list, rename it, or delete it.
values	The values to store in the 2D list, entered row by row.

Example

cuando empezó
[Display an item from a 2D list.]
establecer [my_2d_list v] a ([1][Red]) ([2] [Green])
imprimir (artículo (1) (2) de [my_2d_list v]) ▶

length of 2D list

The length of 2D list block reports the number of rows or columns in a 2D list.

The Length of 2D List reporter block.

longitud de [my2DList v] [rows v]

Parameter	Description
variable	The 2D list variable to check the length of. Users can select an existing 2D list, rename it, or delete it.
rows/columns	Whether to return the number of rows or column.

Example

cuando empezó
[Set a 2D list and print the number of rows it has.]
establecer [my_2d_list v] a ([1][Red]) ([2] [Green])
imprimir (longitud de [my_2d_list v] [rows v]) ▶