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function b= my_de2bi(d, msbflag, n) 
 
%This is the function to convert decimal to binary. here b is the binary 
%output where non-negative decimal vector d is the input data. Each row of 
%the binary matrix b is corresponds to the one element of d. The first 
%element in the row of b signifies LSB. If d is the matrix rather than row 
%and coulmn vector then, convert to coulmn vector.  
 
% here two optional parameter i am using msbflag and n. msbflag determines 
% the output orientation, it has two possible values right_msb and 
% left_msb. if the left_msb id given then the orientation of the bits are 
% just flip i.e. display the msb to the left and right_msb is for the default. 
% n defines how many digits(coulmn) are output. 
 
%santosh shah, The LNM IIT Jaipur (India)(santosh.jnt@gmail.com) 23/04/07 
 
%process for decibel to binary conversion 
 
if nargin < 2 
    msbflag = 'right_msb';  
end % by default msb bit is at the right side 
 
% Convert d to column if necessary 
d = d(:); 
 
% Find minimum number of digits needed to represent the input. If n is 
% specified, use it but only if its >= the required minimum; otherwise 
% raise an error.  
nmax = ceil(log2(max(d))); 
if (nargin < 3) 
    n = nmax; 
elseif n < nmax 
    error('Specified number of columns in output matrix is too small.'); 
end 
 
%checking wheter d is integer or not. 
if ~all(d == floor(d)) 
    error('messege data should be a +ve integer.'); 
end 
 
%allocating space for output data 
b = zeros(length(d),n) ; 
 
% Convert to binary. Loop over the entries of d, and for each entry, first 
% get the lsb, and then keep right shifting by dividing by 2 until the 
% number is zero. 
for k = 1:length(d) 
    x = d(k); 
    l = 1;      % Indicates the bit we are currently looking at 
     
    while x > 0 
         
        % Extract lsb, shift x to the right and update index 
        b(k, l) = bitand(x, 1); 
        x = floor(x / 2); 
        l = l + 1; 
    end 
end 
 
 
%checking the condition of msbflags  
switch(msbflag) 
    case 'left_msb' 
        b = fliplr(b); 
    case 'right_msb' 
        %leave as same 
    otherwise 
        error('Invalid value of MSBFLAG'); 
end