function y = isletter(x)
%MATLAB Code Generation Library Function

%   Limitations:
%   Input values from the 'char' class must be in the range 0-127.

%   Copyright 1984-2014 The MathWorks, Inc.
%#codegen

eml_invariant(nargin > 0, ...
    'MATLAB:minrhs');
if ischar(x)
    coder.internal.prefer_const(x);
    y = isstrprop(x,'alpha');
else
    y = false(size(x));
end
