Random Block

This block generates a random number. You can use random numbers to create unpredictable behavior by your robot. For instance, if you use a data wire to connect a Random block to the Duration plug of a Move block's data hub, your robot might go forward for four seconds one time but then eight seconds the next time you run the program.

The random number will be generated between (and including) minimum and maximum limits that you set. If you want to generate random numbers between 5 and 10, and including 5 and 10 as the possible numbers, set the minimum value to 5 and the maximum value to 10. If you don’t want 5 or 10 to be within the set of possible random numbers, choose a minimum value of 6 and a maximum value of 9.

Set the minimum and maximum limits either by using the slider or by typing values into the input box. To get a dynamic number, attach input data wires to the block’s data hub.

Output for the block (i.e., the random number) can only be sent through a data wire from the output value (#) plug. (See the Data Hub section below for more information.)

1. This block’s data hub will open automatically when the block is attached to a sequence beam.

Configuring the Random Block

1. Set the minimum and maximum limits either by using the two sliders handles or by typing in numbers. The upper limit of the slider is marked as 100, but if an upper limit is typed into the value box, it can be above 100. You can also type a negative number into the minimum limit box; this will override the slider. To set the minimum and maximum limits dynamically, attach input data wires to the block’s data hub.

Configuring the Random block’s Data Hub

You can control the Random block dynamically by connecting data wires (from other blocks’ data hubs) to the Random block’s data hub.

Open a block’s data hub by clicking the tab at the lower left edge of the block after it has been placed on the work area.

Data wires carrying input information to a block are connected to the plugs on the left side of its data hub. Data wires carrying output information are connected to the plugs on the right side.

[A] Input plug
[B] Output plug
[C] Number data wire (yellow)
[D] Logic data wire (green)
[E] Text data wire (orange)
[F] Broken data wire (gray)

Passing data from the input plug to the output plug

If an input plug has a corresponding output plug (see A above), the input data will pass through from the input plug to the output plug without being changed. In this case, you can only use the output plug if the input plug is connected to an input data wire; connecting an output data wire to such an output plug without a connected input data wire will cause the output data wire to be "broken" (and colored gray).

Data wires carry specific types of data

Each data wire carries a specific type of data between blocks. For example, if a data wire is dragged from a logic plug on a block’s data hub, it can only be connected to a logic plug on another block’s data hub. The chart below shows what kind of data each plug can accept or send out.

Data wire colors

Data wires are identified with specific colors: wires carrying number data are colored yellow, wires carrying logic data are colored green, and wires carrying text data are colored orange.

"Broken" data wires

If you try to connect a data wire to a plug of the wrong data type, the data wire will be broken (and colored gray). You will not be able to download your program if a data wire is broken.

If you click a broken wire you can read why it is broken in the small help window in the lower right corner of the work area.

Data must be within the possible range of the plug

If an input data wire transmits a value outside the possible range of the plug it is connected to, the block will either ignore the value or change it to a value within its range. For plugs that allow just a few input values (example: just 0, 1, or 2), the plug will ignore the input if a value arrives outside its range.

For plugs that accept larger input ranges (example: 0 – 100), the plug will force any input outside its range to fit. For example, if a Move block’s Power plug receives an input value of 150, the block will change the input value to 100 (i.e., a number within the Power plug’s range).

This chart shows the different characteristics of the plugs on the Random block’s data hub:

	Plug	Data Type	Possible Range	What the Values Mean	This Plug is Ignored When...
	A	Number	0 - 32767	Lower limit
	B	Number	0 - 32767	Upper limit
	Number	Number	Lower limit - Upper limit	A random value between lower and upper limits (including the limit values)