MATLAB: Fgetl, Fscanf, Fgets, Fprintf Execution Time

binaryfgetlfgetsfprintffscanfpreallocationreshapeserial

Hi, I have created a serial communication for send and receive data. However, these function allows sending data to the serial port and retrieving the data from it. I understood it need some times (few seconds) for the function to execute. However, when i loop it. The time will be increase exponentially. I believe it cause hanging to my code. Can someone have better suggestion to replace fprintf for sending and fgetl for receiving binary bits to allow faster execution time? Many thanks in advance
Here is the coding for send and receive: For Send:
%Open the file
fid=fopen('XXX.mp3','rb'); % Open a file inside MATLAB any music file.
    A=fread(fid,'uint16');      % Display the data in uint16
    B=dec2bin(A);    % Change decimal (0-65535) into 16 binary bits and store in matrix (Mx1) matrix
    F=B';      % Transpose it so it will not in matrix format 
    [M N]=size(A);              %Determine the size
    looptimes=fix(M/5000);
    last=rem(M, 5000);
send_count=1;
loop_count=0;
C=[];
 for i=1+5000*(send_count-1):5000*send_count    %To send data 5kB
     C=[C F((-15+16*(i)):16*(i))];              %16bits everytime loop and send
end
fprintf(s,C)                                    %Send to the serial port
send_count=1+send_count;
For receive:
file=[];
received_count=1;
    loop_count=0;
    while strcmp(s.PinStatus.ClearToSend,'on')
        s.RequestToSend='on';
        received=fgetl(s);                      %To receive bits from serial port
        file=[file received];       %Concatenate back
        received_count=received_count+1;
size_byte=fix(size(file)/32);                   % The size of the file
        M=size_byte(2);
        Video_bin=zeros(M,1);
for j=1:M % To arrange back the file
    b=16*(j);
    a=-15+b;
             Video_bin= [Video_bin;file(a:b)];
         end
              Video_dec=bin2dec(Video_bin);     % From binary to decimal
              fid1=fopen (Save_file, 'wb');     % Form back the original file
              count=fwrite(fid1, Video_dec, 'uint16');

Best Answer

Use the profiler to identify the bottlenecks and did you preallocate (if possible) when importing?
EDIT
About preallocation and taking as an example the code you posted below:
% Example inputs
A1 = [];
M = 6000;
B = randi([0,1],1,16*M);
% Manual reshape WITHOUT preallocation
tic
for j = 1:M
    b = 16*(j);
    a = -15+b; 
    A1 =  [A1; B(a:b)];
end
toc
% Manual reshape WITH preallocation
tic
A2 = zeros(M,16);
for j = 1:M
    b = 16*(j);
    a = -15+b; 
    A2(j,:) =  B(a:b);
end
toc
% Reshape
tic
A3 = reshape(B,16,M).';
toc
A1: Elapsed time is 1.708695 seconds.
A2: Elapsed time is 0.014439 seconds.
A3: Elapsed time is 0.001066 seconds.
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