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@(@\newcommand{\W}[1]{ \; #1 \; } \newcommand{\R}[1]{ {\rm #1} } \newcommand{\B}[1]{ {\bf #1} } \newcommand{\D}[2]{ \frac{\partial #1}{\partial #2} } \newcommand{\DD}[3]{ \frac{\partial^2 #1}{\partial #2 \partial #3} } \newcommand{\Dpow}[2]{ \frac{\partial^{#1}}{\partial {#2}^{#1}} } \newcommand{\dpow}[2]{ \frac{ {\rm d}^{#1}}{{\rm d}\, {#2}^{#1}} }@)@
Common Variables Used by Multi-threading Sum of 1/i

Purpose
This source code defines the common include files, defines, and variables that are used by the summation that defines the harmonic series @[@ 1 + 1/2 + 1/3 + ... + 1/n @]@

Source



# include <cppad/cppad.hpp>
# include "harmonic.hpp"
# include "team_thread.hpp"
# define MAX_NUMBER_THREADS 48

namespace {
     using CppAD::thread_alloc; // fast multi-threadeding memory allocator

     // Number of threads, set by previous call to harmonic_time
     // (zero means one thread with no multi-threading setup)
     size_t num_threads_ = 0;

     // value of mega_sum, set by previous call to harmonic_time.
     size_t mega_sum_;

     // structure with information for one thread
     typedef struct {
          // index to start summation at (worker input)
          // set by previous call to harmonic_setup
          size_t start;
          // index to end summation at (worker input)
          // set by previous call to harmonic_setup
          size_t stop;
          // summation for this thread
          // set by worker
          double sum;
          // false if an error occurs, true otherwise
          // set by worker
          bool   ok;
     } work_one_t;

     // vector with information for all threads
     // (use pointers instead of values to avoid false sharing)
     work_one_t* work_all_[MAX_NUMBER_THREADS];
}

Input File: example/multi_thread/harmonic.cpp