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landmarkInfo

Retrieve landmark information

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    Syntax

    Info = landmarkInfo(slamObj)
    Info = landmarkInfo(slamObj,landmarkIndex)

    Description

    example

    Info = landmarkInfo(slamObj)retrieves landmark information from the ekfSLAM object as a table that contains each landmark number along with its position and state index.

    Info = landmarkInfo(slamObj,landmarkIndex) retrieves landmark information for only those landmarks specified by landmarkIndex.

    Examples

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    Open Live Script

    Specify the initial vehicle state.

    initialState = [1; -2; 0.1];

    Specify the initial landmark positions.

    landmarkPosition = [15.8495; -12.9496;
                    25.2455; -15.4705;
                    37.5880;   3.1023;
                    16.5690;   2.7466];

    Specify the initial vehicle state covariance.

    initialStateCovar = diag([0.1*ones(1,3) 1.1*ones(1,8)]);

    Create an ekfSLAM object with initial state and initial state covariance.

    ekfSlamObj = ekfSLAM('State',[initialState; landmarkPosition], ...
                     'StateCovariance',initialStateCovar)
    ekfSlamObj = 
  ekfSLAM with properties:

                 State: [11x1 double]                    
       StateCovariance: [11x11 double]                   
        MaxNumLandmark: Inf                              
    StateTransitionFcn: @nav.algs.velocityMotionModel    
          ProcessNoise: [2x2 double]                     

           MeasurementFcn: @nav.algs.rangeBearingMeasurement           
    InverseMeasurementFcn: @nav.algs.rangeBearingInverseMeasurement    

     DataAssociationFcn: @nav.algs.associateMaxLikelihood    
    MaxAssociationRange: Inf

    Get the information for all the landmarks.

    info = landmarkInfo(ekfSlamObj)
    info=4×3 table
    landmark number    landmark state index    landmark position
    _______________    ____________________    _________________

           1                  4     5           15.85    -12.95 
           2                  6     7          25.245    -15.47 
           3                  8     9          37.588    3.1023 
           4                 10    11          16.569    2.7466

    Input Arguments

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    EKF SLAM object, specified as an ekfSLAM object.

    Indices of landmarks for which to retrieve information, specified as an N-element column vector of landmark numbers in the state vector or an N-by-2 matrix of exact positions of landmarks in the state vector. N is the number of landmarks.

    Data Types: single | double

    Output Arguments

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    Landmark information, returned as a table.

    Extended Capabilities

    C/C++ Code Generation
    Generate C and C++ code using MATLAB® Coder™.

    Version History

    Introduced in R2021b

    See Also

    Objects

    Functions