num2lab(x,formstr,prestr,poststr)

function label = num2lab(x,formstr,prestr,poststr)
% NUM2LABEL Converts a numeric vector into a cell vector of strings.
% LABEL = NUM2LABEL(X, F, PREFIX, POSTFIX) converts the vector X into a cell array of strings,
%   where each cell contains a string representation of X(j), prefixed by PREFIX
%   and postfixed by POSTFIX. The used format for numeric to string conversion
%   is the one provided in F.
%   As an example, F may be '%d', '%.2f', '%+0.3f', etc... 
%   Valid formats are the same accepted by SPRINTF.
%
%   This function can be helpful in generating legends and ticklabels.
%
%     % Examples
%     figure
%     plot(rand(10,3));
%     legend_label=num2lab(1:3,'%d','Random signal #');
%     title('Random Fast Fourier Transform amplitude coefficients');
%     label=num2lab(1:10,'%d','Coeff #');
%     set(gca,'xticklabel',label);
%     legend(legend_label);
%
% See also CELLSTR, NUM2STR, SPRINTF

% Copyright: Marco Cococcioni, 2008
% $Revision: 1.1 $  $Date: 2008/07/16 11::02:00 $
%--------------------------------------------------------------------------

if nargin < 1,
    disp('At least the vector x has to be provided. Running in demo mode.');
    disp('Press a key to continue...');
    pause
    figure
    plot(rand(10,3));
    legend_label=num2lab(1:3,'%d','Random signal #');
    title('Fast Fourier Transform randomly generated amplitude coefficients');
    label=num2lab(1:10,'%d','Coeff #');
    set(gca,'xticklabel',label);
    legend(legend_label);
    return
end
if nargin < 2,
    formstr='%d';
end
if nargin < 3,
    prestr = '';
end
if nargin < 4,
    poststr = '';
end

if not(isvector(x)),
    error ('Error: x must be a vector');
end

label = cellstr(num2str(x(:), [prestr formstr poststr]));