why does matlab tell me that the "chop" command doesn't exist?

why does matlab tell me that the chop command doesn't exist?

Answer 1

[per isakson]

Make sure that you have the Control System Toolbox. chop() is a function in that toolbox.

>> product_info = ver('control')
product_info = 
  struct with fields:
       Name: 'Control System Toolbox'
    Version: '10.5'
    Release: '(R2018b)'
       Date: '24-May-2018'
>>

Maybe chop() is removed. It was obsolete in R2018b.

>> which chop -all
C:\Program Files\MATLAB\R2018b\toolbox\control\ctrlobsolete\chop.m
 

[Walter Roberson]

Ah, it still exists in R2020a; I missed this one.

[Bodo Christian]

I checked and the Control Sistem Toolbox is not there. How do I install it?

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/101885-how-do-i-install-additional-toolboxes-into-an-existing-installation-of-matlab

Note that you will need to be licensed for the toolbox.

You should also have a look at the round() call and consider what behavior you need. For example if you have chop(1.2468,2) do you want 1.25 or do you want (the closest representable number to) 1.24?

[Bodo Christian]

thanks I managed to install the Tool. I have an academic license because I am studying at the Politecnico of Turin. The command was for use in an exercise. I'm at the first approach with matlab thanks to everyone for the answers.

Answer 2

[Walter Roberson]

MATLAB does not contain any chop() function, unless it is a method for some object that I cannot think of at the moment.

Perhaps you want https://www.mathworks.com/matlabcentral/fileexchange/70651-chop

Answer 3

[Steven Lord]

Cleve's original version of MATLAB had a chop command as you can see from the user's guide, but I'm not sure there is such a command in any MathWorks product right now. Did you perhaps want to use Professor Nick Higham's File Exchange submission? If so you'll need to install that add-on -- the easiest way to do that is to use Add-On Explorer.