Error meassge while using wavread and audioread

This is a code for computing mfcc.I'm getting error as

'Undefined function 'wavread' for input arguments of type 'char'.'

When audioread is used instead of wavread it is shown that 'Too many output arguments.'

Could anybody help me resolving the issue?

 % Define variables
    Tw = 25;                % analysis frame duration (ms)
    Ts = 10;                % analysis frame shift (ms)
    alpha = 0.97;           % preemphasis coefficient
    M = 20;                 % number of filterbank channels 
    C = 12;                 % number of cepstral coefficients
    L = 22;                 % cepstral sine lifter parameter
    LF = 300;               % lower frequency limit (Hz)
    HF = 3700;              % upper frequency limit (Hz)
   wav_file = 'sp10.wav';  % input audio filename
N = 9;
    P = 7;
    file_name_array = {'a','d','f','h','n','sa','su'};
    
    for i=1:N
        for k=1:P
   
        wav_file = char(strcat(dir_path,file_name_array(k),'0',num2str(i)));
    
%     for i=1:
    % Read speech samples, sampling rate and precision from file
    [ speech, fs, nbits ] = wavread( wav_file );
% Feature extraction (feature vectors as columns)
    [ MFCCs, FBEs, frames ] = ...
                    mfcc( speech, fs, Tw, Ts, alpha, @hamming, [LF HF], M, C+1, L );

Answer 1

[KSSV]

Try treplacing this line:

wav_file = char(strcat(dir_path,file_name_array(k),'0',num2str(i)));

with

wav_file = [dir_path,filesep,file_name_array(k),'0',num2str(i)];

Also read about fullfile.