.. _program_listing_file_lib_utilities_math_numeric.ipp:

Program Listing for File math_numeric.ipp
=========================================

|exhale_lsh| :ref:`Return to documentation for file <file_lib_utilities_math_numeric.ipp>` (``lib/utilities/math_numeric.ipp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // ---------------------------------------------------------------------
   // This file is part of falcon-core.
   //
   // Copyright (C) 2015, 2016, 2017 Neuro-Electronics Research Flanders
   //
   // Falcon-server is free software: you can redistribute it and/or modify
   // it under the terms of the GNU General Public License as published by
   // the Free Software Foundation, either version 3 of the License, or
   // (at your option) any later version.
   //
   // Falcon-server is distributed in the hope that it will be useful,
   // but WITHOUT ANY WARRANTY; without even the implied warranty of
   // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   // GNU General Public License for more details.
   //
   // You should have received a copy of the GNU General Public License
   // along with falcon-core. If not, see <http://www.gnu.org/licenses/>.
   // ---------------------------------------------------------------------
   
   #include <vector>
   
   template <typename T> std::vector<T> linspace(T min, T max, std::size_t n) {
   
     std::vector<T> result(n);
     auto step = (max - min) / (n - 1);
   
     for (std::size_t i = 0; i < n; i++) {
       result[i] = min + i * step;
     }
   
     return result;
   }
   
   template <typename ForwardIterator>
   double nan_sum(ForwardIterator first, ForwardIterator last) {
   
     bool all_nan = true;
     double result = 0;
   
     for (; first != last; ++first) {
       if (!std::isnan(*first)) {
         result += *first;
         if (all_nan) {
           all_nan = false;
         }
       }
     }
     if (all_nan) {
       return std::nan("");
     }
     return result;
   }
   
   template <typename ForwardIterator>
   double nan_mean(ForwardIterator first, ForwardIterator last, int n_elem_input) {
   
     std::size_t n_elem;
     double acc = 0;
     std::size_t nan_counter = 0;
   
     if (n_elem_input < 0) {
       n_elem = std::distance(first, last);
     } else {
       n_elem = n_elem_input;
     }
   
     if (n_elem < 1) {
       return 0;
     }
   
     std::size_t it_sum = 0;
     for (; first != last; ++first) {
       if (!std::isnan(*first)) {
         acc += *first;
         ++it_sum;
       } else {
         ++nan_counter;
       }
     }
     if (nan_counter == n_elem) {
       return std::nan("");
     }
   
     double ret = acc / (n_elem - nan_counter);
   
     return ret;
   }