Matlab error when playing a sound - matlab

Question

I'm using matlab gui, I'm recording a sound then save it in a folder in c, then display the recorded sound that are in the folder in a listbox when I press play on the sound wav. Matlab gives an error the error is :
************Error using audioread (line 74)**
***The filename specified was not found in the MATLAB path.
Error in Monitoring_System>play_Callback (line 178)
[q, Fs] = audioread(thisstring);
Error in gui_mainfcn (line 95)
feval(varargin{:});
Error in Monitoring_System (line 42)
gui_mainfcn(gui_State, varargin{:});
Error in #(hObject,eventdata)Monitoring_System('play_Callback',hObject,eventdata,guidata(hObject))
Error while evaluating uicontrol Callback*************
-The record code:
format shortg
c = clock;
fix(c);
a=num2str(c);
year=strcat(a(1),a(2),a(3),a(4),a(5));
month=strcat(a(19),a(20));
day=strcat(a(33),a(34));
hour=strcat(a(48),a(49));
min=strcat(a(63),a(64));
sec=strcat(a(74),a(75));
name=strcat(year,'-',month,'-',day,'-',hour,'-',min,'-',sec);
fullpath=fullfile('c:\monitoringsystem',name);
wavwrite(y,44100,fullpath);
y=[];
The code to diplay them in the listbox:
d = dir('C:\monitoringsystem\*.wav'); %get files
set(handles.listbox1,'String',{d.name})
The code to play the sound that is chosen from the listbox:
allstrings = cellstr( get(handles.listbox1, 'String') );
curvalue = get(handles.listbox1, 'Value');
thisstring = allstrings{curvalue};
[q, Fs] = audioread(thisstring);
soundsc(q,44100);
Any help how to solve this problem, with keeping to save in a specific folder. I copied the recorded sound to the matlab folder and then pressed play in the gui for that wav sound it didin't give any error.

Answer 1

Did you try debugging this and seeing what d contains after selecting a file?
As per the documentation, d = dir('C:\monitoringsystem\*.wav'); returns a struct with the following fields: name, date,bytes, isdir, datenum (at least on MATLAB 2015a). Although {d.name} gives you the filename correctly, you should note that this is a relative path only, so MATLAB doesn't where to look for the file unless it's in the active directory.
I'm not entirely sure why you went through all the trouble with allstrings, curvalue, and thisstring, but if I understand correctly what you're trying to do, I would suggest one of two approaches:
Define the default path (i.e. C:\monitoringsystem) in a constant, and then use it when saving\loading:
DEFAULT_PATH = `C:\monitoringsystem`; %// Definition
...
fullpath = fullfile(DEFAULT_PATH,name); %// When saving
...
d = dir(fullfile(DEFAULT_PATH,'*.wav')); %// When listing files
...
[q, Fs] = audioread(fullfile(DEFAULT_PATH,{d.name})); %// When reading a file
Using uigetfile:
[FileName,PathName] = uigetfile('*.wav','Select the WAV file');
FullPath = fullfile(PathName,FileName);
(and then the rest is very similar to the 1st case)