Gate

R2026b

Gate in fault tree documents

Since R2026b

Description

Gate objects represent gates in Safety Analysis Manager fault tree documents. Use Gate objects to configure gate properties.

Creation

To create a Gate object:

• Use the createGate function on another Gate object. Each fault tree contains at least one Gate object.

• Use the getGate function on a FaultTreeDocument object.

• Get the Gates property of a FaultTreeDocument or FaultTree object.

• Get the Gate property of a TransferGate object.

• Get the Inputs property of a Gate object and filter for only Gate objects.

Properties

Type — Gate type

"or" (default) | "and" | "not" | "xor" | "voting"

Gate type, specified as one of these options:

Value	Description
"or"	A logical OR gate that calculates the intersection of the input unavailabilities and frequencies.
"and"	A logical AND gate that calculates the union of the input unavailabilities and frequencies.
"not"	A logical NOT gate that calculates the probability that an input does not occur. For example, if the input probability is 1, the NOT gate returns a probability of 0. You can specify only one input to this gate.
"xor"	A logical exclusive OR gate that calculates the probability that only one event occurs. You can specify only two inputs to this gate.
"voting"	A voting algorithm that calculates the probability that the specified number of the inputs or more occurs. To specify the number of inputs that must be true, define the k property in the FailureProperties object assigned to this gate.

Data Types: enumeration

Label — Gate label

"GATE" (default) | string scalar | character vector

Gate label, specified as a string scalar or character vector. Each gate must have a unique label. If you create another gate with the default label, the next addition uses the default label with an appended number. Each new gate increments the number, for example, GATE1, GATE2, and so on.

Data Types: char | string

Description — Gate description

"" (default) | string scalar | character vector

Gate description, specified as a string scalar or character vector.

Data Types: char | string

ComputeProperties — Whether to calculate failure properties and cutsets

false or 0 (default) | true or 1

Whether to calculate failure properties and cutsets at the gate, specified as a numeric or logical 0 (false) or 1 (true).

Data Types: logical

Inputs — Gate inputs

Read-only: heterogeneous array of Event, Gate, and TransferGate objects

This property is read-only.

Gate inputs, represented as a heterogeneous array of Event, Gate, and TransferGate objects. To assign an event to a gate, use the addEvent function. To assign another gate to this gate, use the createGate function. To assign a transfer gate to this object, use the createTransferGate function.

CutSets — Cutsets that enable gate

Read-only: array of CutSet objects

This property is read-only.

Cutsets that enable this gate, represented as an array of CutSet objects. Each cutset includes the events and transfer gates that enable this gate. If the cutset includes a transfer gate that transfers to another tree, the cutset does not include the inputs in the other tree.

To generate the cutsets in this property, use the evaluate function on the fault tree document that contains this gate.

FailureProperties — Failure properties

Read-only: FailureProperties object

This property is read-only.

Failure properties calculated at the gate, represented as a FailureProperties object. This property is empty if the fault tree document is not evaluated or the ComputeProperties property of the Gate object is false.

ImportanceMeasures — Importance measures

Read-only: array of ImportanceMeasures objects

This property is read-only.

Importance measures of the input events, represented as an array of ImportanceMeasures objects. This property includes the importance measures for each event that contributes to the failure properties calculated at this gate. For example, if the top-level gate has an input gate, and the input gate has two input events, the importance measures of the top-level gate includes both events.

This property is empty if the fault tree document is not evaluated or the ComputeProperties property of the Gate object is false.

IncomingTransfer — Transfer gates that retrieve gate

Read-only: array of TransferGate objects

This property is read-only.

Transfer gates that retrieve this gate as their input, represented as an array of TransferGate objects.

Object Functions

acceptAllChanges	Accept detected changes to linked artifacts in Safety Analysis Manager
addEvent	Add existing event to fault tree gate
addFlag	Add flag to Safety Analysis Manager spreadsheet cell or row
clearFlags	Clear flags in Safety Analysis Manager spreadsheet and fault tree document elements
createEvent	Add event to fault tree document or gate
createGate	Add gate to gates in fault tree
createTransferGate	Add transfer gate to fault tree gate
deleteInput	Delete input of fault tree gates
getChanges	Get changed artifacts linked to artifacts in Safety Analysis Manager
getFlags	Retrieve flags from Safety Analysis Manager documents
getLinks	Get links associated with spreadsheet cell or row in Safety Analysis Manager
navigate	Navigate to elements in Safety Analysis Manager documents and changed artifacts

Examples

Add a Gate to the Top-Level Gate of a Fault Tree

Create a new fault tree document in the Safety Analysis Manager and get the FaultTree object.

myTreeDoc = safetyAnalysisMgr.newDocument("fault-tree");
myFaultTree = myTreeDoc.FaultTrees(1);

Get the gate that corresponds to the top-level gate of the tree.

myTopGate = myFaultTree.Gates(1);

Add an OR gate to the top-level gate.

myNewGate = createGate(myTopGate);

Version History

Introduced in R2026b