Why does MATLAB r2016a not recognize "cheby1" as a function?

I wrote a code implementing a Chebyshev filter which worked fine in my previous version of MATLAB r2013a. I recently had to update to r2016a and the "cheby1" function is no longer recognized. Why is this the case?

Answer 1

[Stephen23]

The function cheby1 is part of the Signal Processing Toolbox. Do you have this toolbox installed, and a valid license for it ?

To check, run this command in your command window, and tell us exactly what it prints:

 ver

[Jacob Mendelson]

Thanks for the quick reply, here is the result.

MATLAB Version: 9.0.0.341360 (R2016a)
MATLAB License Number: ••••••
Operating System: Microsoft Windows 10 Enterprise Version 10.0 (Build 10586)
Java Version: Java 1.7.0_60-b19 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode

[Walter Roberson]

It would have mentioned the Signal Processing Toolbox if you had that installed.

Answer 2

[ilhem ouerghui]

plz I have the same problem; how to know if the signal processing toolbox is installed in my matlab version? I am using matlab r2016b.

[Walter Roberson]

>> ver('signal')
----------------------------------------------------------------------------------------------------
MATLAB Version: 9.1.0.441655 (R2016b)
MATLAB License Number: *****
Operating System: Mac OS X  Version: 10.11.6 Build: 15G1108 
Java Version: Java 1.7.0_75-b13 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode
----------------------------------------------------------------------------------------------------
Signal Processing Toolbox                             Version 7.3         (R2016b)

>> which cheby1
/Applications/MATLAB_R2016b.app/toolbox/signal/signal/cheby1.m