Merge pull request #26 from sethigeet/set_num_thread_automatically

Automatically set the number of threads to max available threads in calculation of std dev

Author: LoPA607

concat

@@ -1,46 +1,48 @@
 // statistics.cpp
-#include "statistics.h"
 #include <omp.h>
+
 #include <cmath>
 #include <iostream>
+
+#include "statistics.h"
+
 // Function to compute the mean
 double computeMean(const std::vector<int>& data, int num_threads) {
-    double sum = 0.0;
+  double sum = 0.0;
 
-    #pragma omp parallel for reduction(+:sum) num_threads(num_threads)
-    for (size_t i = 0; i < data.size(); i++) {
-        sum += data[i];
-    }
+#pragma omp parallel for reduction(+ : sum) num_threads(num_threads)
+  for (size_t i = 0; i < data.size(); i++) {
+    sum += data[i];
+  }
 
-    return sum / data.size();
+  return sum / data.size();
 }
 
 // Function to compute the standard deviation
 double computeStandardDeviation(const std::vector<int>& data, int num_threads) {
-    double mean = computeMean(data, num_threads);
+  double mean = computeMean(data, num_threads);
 
-    double variance_sum = 0.0;
+  double variance_sum = 0.0;
 
-    #pragma omp parallel for reduction(+:variance_sum) num_threads(num_threads)
-    for (size_t i = 0; i < data.size(); i++) {
-        variance_sum += (data[i] - mean) * (data[i] - mean);
-    }
+#pragma omp parallel for reduction(+ : variance_sum) num_threads(num_threads)
+  for (size_t i = 0; i < data.size(); i++) {
+    variance_sum += (data[i] - mean) * (data[i] - mean);
+  }
 
-    double variance = variance_sum / data.size();
-    return std::sqrt(variance);
+  double variance = variance_sum / data.size();
+  return std::sqrt(variance);
 }
 
-
 int main() {
-    // Data set
-    std::vector<int> data = {1, 2, 3, 4, 5, 6};
+  // Data set
+  std::vector<int> data = {1, 2, 3, 4, 5, 6};
 
-    // Number of threads for OpenMP
-    int num_threads = 4;
+  // Number of threads for OpenMP
+  int num_threads = omp_get_max_threads();
 
-    // Calculate and print the standard deviation
-    double stddev = computeStandardDeviation(data, num_threads);
-    std::cout << "Standard Deviation: " << stddev << std::endl;
+  // Calculate and print the standard deviation
+  double stddev = computeStandardDeviation(data, num_threads);
+  std::cout << "Standard Deviation: " << stddev << std::endl;
 
-    return 0;
+  return 0;
 }