title: Getting a 'was not declared in this scope' error
body: <pre><code>void new_doubles(double a, double b, double c)
  {
  double d=max(abs(a), abs(b), abs(c));
  cout&lt;&lt;d;
  }
  </code></pre>
  
  <p>produces this compile time error :</p>
  
  <pre><code>In file included from /usr/local/gcc4.9.0/include/c++/4.9.0/bits/char_traits.h:39:0,
  from /usr/local/gcc4.9.0/include/c++/4.9.0/string:40,
  from /usr/local/gcc4.9.0/include/c++/4.9.0/stdexcept:39,
  from /usr/local/gcc4.9.0/include/c++/4.9.0/array:38,
  from std_lib_facilities_4.h:27,
  from hw4pr4.cpp:1: /usr/local/gcc4.9.0/include/c++/4.9.0/bits/stl_algobase.h: In instantiation of ‘const _Tp&amp;                                           std::max(const _Tp&amp;, const _Tp&amp;, _Compare) [with _Tp = double; _Compare = double]’:
   hw4pr4.cpp:35:36: required from here
  /usr/local/gcc4.9.0/include/c++/4.9.0/bits/stl_algobase.h:264:26: error: ‘__comp’ cannot be used as    a function
  if (__comp(__a, __b))
  </code></pre>
  
  <p><br/> <br/><br/></p>
  
  <p>I dont understand why this error is being produced can anyone help explain what I am doing wrong?</p>