get_param

Get parameter names and values

Syntax

value = get_param(object,parameter)

Description

value = get_param(object,parameter) returns the value value of the specified parameter parameter for the target object specified by object. The target object can be a model, subsystem, library, block, line, port, or bus element port element.

Open or load the related Simulink^® model, subsystem, or library before calling this function.

Examples

Get Block Parameter Value and Model Parameter Value

Load the vdp model.

load_system('vdp');

Get the value for the Expression block parameter.

BlockParameterValue = get_param('vdp/Mu','Multiplication')

BlockParameterValue =

    'Element-wise(K.*u)'

Get the value for the SolverType model parameter.

SolverType = get_param('vdp','SolverType')

SolverType =

    'Variable-step'

Get Root Parameter Names and Values

Get a list of global parameter names by finding the difference between the Simulink root parameter names and the model parameter names.

RootParameterNames = fieldnames(get_param(0,'ObjectParameters'));
load_system('vdp')
ModelParameterNames = fieldnames(get_param('vdp','ObjectParameters'));
GlobalParameterNames = setdiff(RootParameterNames,ModelParameterNames)

GlobalParameterNames =

  79×1 cell array

    {'AccelNoncompliantBlocksRatioLimit'             }
    {'AutoAccelerationStepsPerBlockLimit'            }
    {'AutoAccelerationStepsPerCodegenLimit'          }   
    . . .
    {'CurrentSystem'                                 }

Get the value of a global parameter.

GlobalParameterValue = get_param(0,'CurrentSystem')

GlobalParameterValue =

    'vdp'

Get Model Parameter Names and Values

Get a list of model parameters for the vdp model .

load_system('vdp')
ModelParameterNames = get_param('vdp','ObjectParameters')

ModelParameterNames = 

  struct with fields:

                                              Name: [1×1 struct]
                                               Tag: [1×1 struct]
                                       Description: [1×1 struct]
                                              Type: [1×1 struct]
                                            Parent: [1×1 struct]
                                            Handle: [1×1 struct]
                                            . . .
                       ZeroInternalMemoryAtStartup: [1×1 struct]

Get the current value of the ModelVersion model parameter for the vdp model.

ModelParameterValue = get_param('vdp','ModelVersion')

ModelParameterValue =

    '7.0'

Get List of Blocks and Parameter Value

Get a list of block paths and names for the blocks in the sldemo_fuelsys model. For one of the blocks, get a list of block dialog parameters and the value of a block dialog parameter.

Open the Model a Fault-Tolerant Fuel Control System example.

openExample('simulink_automotive/ModelingAFaultTolerantFuelControlSystemExample');

Get a list of block paths and names for all blocks in the top level of the sldemo_fuelsys model.

BlockPaths = get_param(gcs,'blocks')

BlockPaths =

  21×1 cell array

    {'Callback Button'             }
    {'Constant2'                   }
    {'Constant3'                   }
    {'Constant4'                   }
    {'Constant5'                   }
    {'Dashboard'                   }
    {'EGO Fault Switch'            }
    {'Engine Gas Dynamics'         }
    {'Engine Speed'                }
    {'Engine Speed↵Fault Switch'  }
    {'Engine_Speed_Selector'       }
    {'MAP Fault Switch'            }
    {'MAP_Selector'                }
    {'O2_Voltage_Selector'         }
    {'Scope'                       }
    {'Throttle↵Command'           }
    {'Throttle Angle↵Fault Switch'}
    {'Throttle_Angle_Selector'     }
    {'To Controller'               }
    {'To Plant'                    }
    {'fuel_rate_control'           }

The command outputs a list of block paths and names for all blocks in the top hierarchical level of the current system. If the current system is a subsystem, the command outputs a list of block paths and names for all blocks in the top hierarchical level of the subsystem.

In this example, the current system is sldemo_fuelsys, so the command outputs a list of block paths and names for all blocks in the top hierarchical level of the sldemo_fuelsys system.

Get a list of block paths and names for all blocks in all levels of the sldemo_fuelsys model.

BlockPaths = find_system(gcs,'Type','Block')

BlockPaths =

  188×1 cell array

    {'sldemo_fuelsys/Callback Button'                                                                     }
    {'sldemo_fuelsys/Constant2'                                                                           }
    {'sldemo_fuelsys/Constant3'                                                                           }
    ...
    {'sldemo_fuelsys/fuel_rate_control/fuel_rate'                                                         }

The command outputs a list of block paths and names for all blocks in the top hierarchical level of the current system and in all lower levels of model hierarchy that the current system contains. In this example, the current system is sldemo_fuelsys, so the output is a list of block paths and names for all blocks in the sldemo_fuelsys model.

Get a list of block dialog parameters for the Gain block named RT/Vm. The first argument in the get_param function is the block path and name. Get the block path and name from the BlockPaths cell array.

BlockDialogParameters = get_param(BlockPaths{44},'DialogParameters')

BlockDialogParameters = 

  struct with fields:

                         Gain: [1×1 struct]
               Multiplication: [1×1 struct]
                     ParamMin: [1×1 struct]
                     ParamMax: [1×1 struct]
             ParamDataTypeStr: [1×1 struct]
                       OutMin: [1×1 struct]
                       OutMax: [1×1 struct]
               OutDataTypeStr: [1×1 struct]
                    LockScale: [1×1 struct]
                      RndMeth: [1×1 struct]
    SaturateOnIntegerOverflow: [1×1 struct]
                   SampleTime: [1×1 struct]

Get the value for the Multiplication block parameter.

BlockParameterValue = get_param(BlockPaths{44},'Multiplication')

BlockParameterValue =

    'Element-wise(K.*u)'

Get Block Parameter Value Using Block Handle

Get the value of the Multiplication block parameter of the Gain block named Mu in the vdp model.

Get the handle of the Gain block named Mu in the vdp model using the getSimulinkBlockHandle function. Specify the model and block names by entering 'vdp/Mu' as the input argument. If the vdp model is not loaded, load the model by specifying true as the second input argument to the getSimulinkBlockHandle function.

mublockhandle = getSimulinkBlockHandle('vdp/Mu',true)

mublockhandle =

    5.0001

The handle contains a double, for example, 5.0001. If you display a handle number in the MATLAB^® Command Window, the display might not show all digits of the number. Do not try to use this handle number by manually entering what you see in the display. Instead, assign the handle to a variable and use that variable name to specify the block.

Tip

If you make multiple calls to get_param for the same block, use the block handle instead of repeatedly specifying the full block path as a character vector such as 'vdp/Mu'. You can use the block handle in subsequent calls to get_param or set_param.

To get the value of the Multiplication block parameter, use the get_param function. Specify the block handle as the first input argument and the name of the block parameter as the second input argument.

BlockParameterValue = get_param(mublockhandle,'Multiplication')

BlockParameterValue =

    'Element-wise(K.*u)'

Display Block Types for All Blocks in Model

Get a list of block paths and names for the vdp model.

load_system('vdp')
BlockPaths = find_system('vdp','Type','Block')

BlockPaths =

  14×1 cell array

    {'vdp/Constant'            }
    {'vdp/More Info'           }
    {'vdp/More Info/Model Info'}
    {'vdp/Mu'                  }
    {'vdp/Mux'                 }
    {'vdp/Product'             }
    {'vdp/Scope'               }
    {'vdp/Square'              }
    {'vdp/Sum'                 }
    {'vdp/Sum1'                }
    {'vdp/x1'                  }
    {'vdp/x2'                  }
    {'vdp/Out1'                }
    {'vdp/Out2'                }

Get the value for the BlockType parameter for each of the blocks in the vdp model.

BlockTypes = get_param(BlockPaths,'BlockType')

BlockTypes =

  14×1 cell array

    {'Constant'  }
    {'SubSystem' }
    {'SubSystem' }
    {'Gain'      }
    {'Mux'       }
    {'Product'   }
    {'Scope'     }
    {'Math'      }
    {'Sum'       }
    {'Sum'       }
    {'Integrator'}
    {'Integrator'}
    {'Outport'   }
    {'Outport'   }

Get List of Options for Masked Parameter, Simulink Object, Block Diagram, or Annotation

You can retrieve the list of options for a parameter, Simulink object, block diagram, or annotation using the get_param function with the keyword options.

Get the list of options for a masked parameter. For example, consider the masked Subsystem block in the ACSystem model. Get the list of options for the Subsystem block parameter Show port labels.

openExample('simulink_masking/DesignAMaskDialogBoxExample')
get_param('ACSystem/AC System','options@showportlabels')

ans =

  1×4 cell array

    {'none'}    {'FromPortIcon'}    {'FromPortBlockName'}    {'SignalName'}

Get the list of options for a block parameter. For example, get the list of options for the Icon display parameter of an Inport block.

get_param('ACSystem/In1','options@icondisplay')

ans =

  1×3 cell array

    {'Signal name'}    {'Port number'}    {'Port number and si…'}

Get Evaluated Value of Mask Parameter

You can access the evaluated value of a masked block parameter using the get_param function with the keyword value.

For example, consider the masked Subsystem block in the ACSystem model. Get the evaluated value of the edit parameter on the mask called Room Width (W).

openExample('simulink_masking/DesignAMaskDialogBoxExample')
get_param('ACSystem/AC System','value@W')

ans =

   133

The option to retrieve the evaluated value is limited to mask parameters.

Open the mask of the AC System block by double-clicking the block. The value of the Room Width (W) parameter is the same as the value you get using the get_param function.

Input Arguments

object — Name, path, or handle of object or root

character vector | cell array of character vectors | string array | numeric scalar | 0

Name, path, or handle of object or root, specified as a character vector, cell array of character vectors, string array, numeric scalar, or 0.

How you specify the target object depends on its type.

• Model — Model name or handle.

• Subsystem — Subsystem name or handle.

• Library — Library name or handle.

• Block — Block path or handle.

• Line — Line handle.

• Port — Port handle.

• Bus element port element — Block path of model component with element label. The element can be any element of the port, such as a top-level bus, nested bus, signal, or message.

To specify multiple objects with a common parameter, use a cell array of character vectors, a string array, or an array of handles. All the specified objects must have the specified parameter, otherwise, the function returns an error.

Specify 0 to get root parameter names, including global parameters and model parameters for the current Simulink session.

• Global parameters include Editor preferences and Simulink Coder™ parameters.

• Model parameters include configuration parameters, Simulink Coder parameters, and Simulink Code Inspector™ parameters.

Example: 'vdp/Mu'

Example: 'mymodel/Subsystem1/Out1.nonsinusoidal.saw'

Tips

• If you make multiple calls to get_param for the same block, specify the block with a numeric handle. This method is more efficient than using the full block path with get_param. Use getSimulinkBlockHandle to get a block handle.

• Do not try to manually specify the number of a handle, for example, 5.007, because you usually need to specify more digits than MATLAB displays. Assign the handle to a variable and use that variable name.

Data Types: char | string | double

parameter — Parameter, property, or attribute name

character vector | string scalar

Parameter, property, or attribute name, specified as a character vector or string scalar. Some names are case sensitive.

This table shows special cases.

Specified Parameter	Result
'ObjectParameters'	Parameter names of the specified object as separate fields in a structure array.
'DialogParameters'	Block dialog box parameter names as separate fields in a structure array. If the block has a mask, the function instead returns the mask parameters.

For information about parameters, properties, or attributes, see the programmatic use information on the corresponding reference pages. For example:

• Models — See the configuration parameter reference pages.

• Blocks — See Common Block Properties and block reference pages.

• Ports — See the Signal Properties tool reference page.

• Bus element port elements — See the In Bus Element and Out Bus Element block reference pages.

Example: 'ObjectParameters'

Example: 'Solver'

Example: 'SimulationCommand'

Example: 'Position'

Example: 'NameLocation'

Data Types: char | string

Output Arguments

value — Parameter value

format determined by parameter type

Parameter value, returned in the format determined by the parameter type. If you specify multiple objects, the output is a cell array.

This table shows special cases.

Specified Parameter	Result
'ObjectParameters'	Parameter names of the specified object as separate fields in a structure array.
'DialogParameters'	Block dialog box parameter names as separate fields in a structure array. If the block has a mask, the function instead returns the mask parameters.

If you get the root parameters by specifying get_param(0,'ObjectParameters'), then the output value is a structure array with the root parameter names as separate fields in the structure. Each parameter field is a structure containing these fields:

• Type — Parameter type values are 'boolean', 'string', 'int', 'real', 'point', 'rectangle', 'matrix', 'enum', 'ports', or 'list'.

• Enum — Cell array of enumeration character vector values that applies only to 'enum' parameter types.

• Attributes — Cell array of character vectors defining the attributes of the parameter. Values are 'read-write', 'read-only', 'read-only-if-compiled', 'write-only', 'dont-eval', 'always-save', 'never-save', 'nondirty', or 'simulation'.

Version History

Introduced before R2006a