error with using filter command

Hello Guys,

Am trying to run this piece of code but i end up getting a throw out error with the "filter" function.

Am using Matlab R2018a. Is it a problem with my Matlab version.

A = [1 -2.7607 3.8106 -2.6535 0.9238];
y = filter(1,A,0.2*randn(1024,1));      %Throw out Error: Too many input arguments. 
arcoeffs = arcov(y,4)

Any solution will be appreciated... Thanks in advance

[Walter Roberson]

It works on my system. What shows up for

which filter(1)

[Evans Gyan]

It looks like the filter command does not work for me. Do I need to install some add ons? I have tried again and i keep getting the same error

"Error using filter

Too many input arguments."

[Walter Roberson]

No, filter is basic MATLAB, at least with those kinds of input arguments. https://www.mathworks.com/help/matlab/ref/filter.html

What output do you see when you invoke

which filter

[Evans Gyan]

I get a path to a directory file. Unfortunately i had a file named "filter" in my matlab directory hence the error. I move it to another folder. The throwback error no longer exist.

Thank you very much for your assistance.

[Bjorn Gustavsson]

@Evans Gyan: An (unrequested) advice: After cases where I started running into name-clashes like this I decided to put my matlab-directories at the end of the matlab-path - that made sure that basic matlab-functions never were shaded, and that I instantly understood that my new functions were shaded so I had to change names asap.