Adding the new boost sort library.

example/stringfunctorsample.cpp

@@ -0,0 +1,124 @@
+//! \brief spreadsort string functor sorting example.
+//! \file
+//
+//  Copyright Steven Ross 2009-2014.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//    (See accompanying file LICENSE_1_0.txt or copy at
+//          http://www.boost.org/LICENSE_1_0.txt)
+
+//  See http://www.boost.org/libs/sort for library home page.
+
+// Caution: this file contains Quickbook markup as well as code
+// and comments, don't change any of the special comment markups!
+
+#include <boost/sort/spreadsort/string_sort.hpp>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <algorithm>
+#include <vector>
+#include <iostream>
+#include <fstream>
+#include <string>
+using std::string;
+using namespace boost::sort::spreadsort;
+
+struct DATA_TYPE {
+    string a;
+};
+
+//[lessthan_functor
+
+struct lessthan {
+  inline bool operator()(const DATA_TYPE &x, const DATA_TYPE &y) const {
+    return x.a < y.a;
+  }
+};
+//] [/lessthan_functor]
+
+//[bracket_functor
+struct bracket {
+  inline unsigned char operator()(const DATA_TYPE &x, size_t offset) const {
+    return x.a[offset];
+  }
+};
+//] [/bracket_functor]
+
+//[getsize_functor
+struct getsize {
+  inline size_t operator()(const DATA_TYPE &x) const{ return x.a.size(); }
+};
+//] [/getsize_functor]
+
+//Pass in an argument to test std::sort
+int main(int argc, const char ** argv) {
+  std::ifstream indata;
+  std::ofstream outfile;
+  bool stdSort = false;
+  unsigned loopCount = 1;
+  for (int u = 1; u < argc; ++u) {
+    if (std::string(argv[u]) == "-std")
+      stdSort = true;
+    else
+      loopCount = atoi(argv[u]);
+  }
+  double total = 0.0;
+  //Run multiple loops, if requested
+  std::vector<DATA_TYPE> array;
+  for (unsigned u = 0; u < loopCount; ++u) {
+    indata.open("input.txt", std::ios_base::in | std::ios_base::binary);
+    if (indata.bad()) {
+      printf("input.txt could not be opened\n");
+      return 1;
+    }
+    DATA_TYPE inval;
+    indata >> inval.a;
+    while (!indata.eof() ) {
+      array.push_back(inval);
+      //Inserting embedded nulls and empty strings
+      if (!(array.size() % 100)) {
+        if (inval.a.empty() || !(array.size() % 1000)) {
+          inval.a = "";
+          array.push_back(inval);
+        }
+        else {
+          inval.a[0] = '\0';
+          array.push_back(inval);
+        }
+      }
+      indata >> inval.a;
+    }
+
+    indata.close();
+    clock_t start, end;
+    double elapsed;
+    start = clock();
+    if (stdSort)
+      std::sort(array.begin(), array.end(), lessthan());
+    else
+//[stringsort_functors_call
+      string_sort(array.begin(), array.end(), bracket(), getsize(), lessthan());
+//] [/stringsort_functors_call]
+    end = clock();
+    elapsed = static_cast<double>(end - start);
+    if (stdSort)
+      outfile.open("standard_sort_out.txt", std::ios_base::out |
+                   std::ios_base::binary | std::ios_base::trunc);
+    else
+      outfile.open("boost_sort_out.txt", std::ios_base::out |
+                   std::ios_base::binary | std::ios_base::trunc);
+    if (outfile.good()) {
+      for (unsigned u = 0; u < array.size(); ++u)
+        outfile << array[u].a << "\n";
+      outfile.close();
+    }
+    total += elapsed;
+    array.clear();
+  }
+  if (stdSort)
+    printf("std::sort elapsed time %f\n", total / CLOCKS_PER_SEC);
+  else
+    printf("spreadsort elapsed time %f\n", total / CLOCKS_PER_SEC);
+  return 0;
+}