Why do I receive this error "Invalid data type. Input arrays must be numeric or logical."?

Hi,

I have a couple of .csv files and I am trying to read them first and then filter them out in a loop. But when I use "readtable" to read the .csv file, I receive this error:

Error using filter
Invalid data type. Input arrays must be numeric or logical.

Error in bestalgo_combined_newdata (line 18)
y_n2=filter(b,a,y2);

But when I run the same code with "xlsread" (I know this is not recommended, but still...) I get no error, everything runs fine. Can someone help what's the issue?

I am just adding a part of my code, because I don't think the whole code is relevant, no matter I read one .csv file or several, issue remains.

clearvars;

%Filter design
fl=0;
fh=9000;
fs=40000;
array_pW=zeros(100,1);

y2=readtable('cross talking.csv');
%more file to read, removed%
x=readtable('continuous.csv');

for e=1:100
    fl=fl+50;

    [b,a]=ellip(2, 1, 40, [fl,fh]/(fs/2),'bandpass');

    y_n2=filter(b,a,y2);
    y_h2 = normalize(y_n2, 'range', [-1 1]);
    power2=rms(y_h2)^2;

    %more code, removed...%
end

Can someone help? Thanks.

Answer 1

[Chunru]

It seems file to read the data using "readtable" as shown below.

You can try "dbstop error" before running the code to locate where it goes wrong.

x= readtable("https://www.mathworks.com/matlabcentral/answers/uploaded_files/939564/cross%20talking.csv");
head(x)

ans = 8×1 table
    Var1
    ____

    2671
    2669
    2671
    2668
    2663
    2665
    2663
    2665

[Giggs B.]

Hi Chunru,

using "dbstop error" does not gives me any significant info. I get this:

>> normalized_weighted
Error using filter
Invalid data type. Input arrays must be numeric or logical.

Error in normalized_weighted (line 44)
y_n2=filter(b,a,y2);
 
18  y_n2=filter(b,a,y2);
K>> dbstop if error

[Stephen23]

@Giggs B.: as Chunru wrote you need to call

dbstop if error

before running your code, not after. Then when the error occurs it will then stop in debug mode, so you check all of the inut arguments and run commands, etc.

https://www.mathworks.com/help/matlab/debugging-code.html

[Chunru]

It looks like you use the table as an input to the filter function (you don't show the complete code). You can try to replace "readtable" by "readmatrix".

[Giggs B.]

Thanks, @Chunru. "Readmatrix" works!