hey guys , just started working with ROS and MATLAB for Msc .I am trying to access laser scannerdata from ros But keep getting the following error. Could somebody help me

laserScan=scanHandle;
scanSubCallback=rossubscriber('/scan',{@scanCallback, laserScan});

function [] = scanCallback( ~, LaserScanMsg, laserScan)
laserScan.ranges=LaserScanMsg.ranges;
laserscan.angles=readScanAngles(LaserScanMsg);
laserScan.beta=LaserScanMsg.beta;
laserScan.rmin=LaserScanMsg.rmin;
laserScan.phmin=LaserScanMsg.phmin;
end

%scanhandle I defined in a.m file

classdef scanHandle < handle
    properties
        ranges=0
        angles =0
        beta = 0.5;
        robotradius=0.2;
        rmin=0;
        phimin=0;
    end
    ...
end

THIS IS THE ERROR I GET

Unrecognized method, property, or field 'ranges' for class

'ros.msg.sensor_msgs.LaserScan'.

Error in LiveEditorEvaluationHelperE479036005>scanCallback (line 25)

laserScan.ranges=LaserScanMsg.ranges;

Error in ros.internal.SubscriberCallbackHandler/processNewMessage

(line 58)

feval(obj.NewMessageCallbackFcn, ...

Unrecognized method, property, or field 'ranges' for class

'ros.msg.sensor_msgs.LaserScan'.

Answer 1

[Walter Roberson]

You have to use Ranges not ranges.

[NADEEM SHOUKATH]

Thank you , but now I get the following error for Beta:-

Error in

LiveEditorEvaluationHelperE479036005>scanCallback

(line 27)

laserScan.Beta=LaserScanMsg.Beta;

Error in

ros.internal.SubscriberCallbackHandler/processNewMessage

(line 58)

feval(obj.NewMessageCallbackFcn,

...

[Walter Roberson]

https://www.mathworks.com/help/ros/ref/laserscan.html

LaserScanMsg objects do not have beta, rmin, or phmin .

laserscan.angles=readScanAngles(LaserScanMsg);

Is it possible that beta, rmin, phmin are being returned by readScanAngles ?

[NADEEM SHOUKATH]

yup you are absolutely correct , thanks a million !