using <random> library

[mrtn kvn]

Hi everybody
I'm using Borland C++ 5.02 on windows 7.
I want to generate random numbers according to different distributions such as normal, uniform and ...
I found that I have to use <random.h> library. So, at first I entered the example code in http://www.cplusplus.com/reference/random/uniform_int_distribution/.
the code is as follows:

#include <random>
void main()
{
  const int nrolls = 10000; // number of experiments
  const int nstars = 95;    // maximum number of stars to distribute

  default_random_engine generator;                    
  uniform_int_distribution <int> distribution(0,9);  

  int p[10]={0};

  for (int i=0; i<nrolls; ++i) {
    int number = distribution(generator);           
    ++p[number];
  }

  cout << "uniform_int_distribution (0,9):" << endl;
  for (int i=0; i<10; ++i)
    cout << i << ": " << string('*',p[i]*nstars/nrolls) << endl;

  return;
}

and when I compile the code I receive these errors:

Info :Compiling C:\BC5\BIN\foo.cpp
Error:  test of distr.cpp(7,34):Undefined symbol 'default_random_engine'
Error:  test of distr.cpp(7,34):Statement missing ;
Error:  test of distr.cpp(8,29):Undefined symbol 'uniform_int_distribution'
Error:  test of distr.cpp(8,33):Expression syntax
Error:  test of distr.cpp(13,31):Call to undefined function 'distribution'
Error:  test of distr.cpp(13,41):Undefined symbol 'generator'

I was wondering if anyone might be able to help me.

[coder777]

In the example there are std:: where necessary.
So either you add them or you write using namespace std; at the top of your file.

[Chervil]

According to wikipedia, Borland C++ 5.02 was released in 1999.
The <random> feature was introduced as part of C++11, that is a 2011 update to the standard.

I suggest you leave behind the outdated Borland compiler and switch to an up-to-date IDE/compiler such as code::blocks or Orwell DevC++ which will give you access to these most recent C++ features.

http://www.codeblocks.org/
http://orwelldevcpp.blogspot.com/

[mrtn kvn]

thank you so much

[mrtn kvn]

Hi again!

I Installed (codeblocks-13.12mingw-setup-TDM-GCC-481.exe) from sourceforge.net while it's release date is 27 Dec 2013.

I entered the aforementioned code and received this error message:

c:\program files (x86)\codeblocks\mingw\lib\gcc\mingw32\4.8.1\include\c++\bits\c++0x_warning.h|32|error: #error This file requires compiler and library support for the ISO C++ 2011 standard. This support is currently experimental, and must be enabled with the -std=c++11 or -std=gnu++11 compiler options.

what should I do?
I appreciate you if you help me.

[MiiNiPaa]

settings → compiler → check Have g++ follow the C++11 ISO C++ language standard

[mrtn kvn]

Thanks a lot