DaniWeb Forum Index > Software Development > C++

C++ RSS

Counting the frequency of random numbers

Please support our C++ advertiser: Intel Parallel Studio Home

Thread Solved

•

Join Date: Apr 2007

Posts: 4

Reputation: Armfelt is an unknown quantity at this point

Solved Threads: 0

Armfelt

Offline

Newbie Poster

Counting the frequency of random numbers

Apr 21st, 2007

Hello everyone, this is my first post.
As can be quite rightly guessed, I am new to C++ and struggling with some coursework.

My task is to produce a program that prints out 5000 random numbers between 1-5, also printing out the frequency of each given number.

I have searched for an answer as to how this might be done, and I believe it might have something to do with Arrays, could someone please give me a hint whether this is right?

Here is my code so far

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <vcl.h>
#include <iostream.h>
 
using namespace std;
 
int main(void)
{
    int random_integer;
    for(int numero=0; numero < 5000; numero++){
    random_integer = 0 + int(6 * rand()/(RAND_MAX+1.0));
    cout << random_integer << endl;
}
    cin.get();
    return 0;
}
#include <vcl.h>
#include <iostream.h>

using namespace std;

int main(void)
{
    int random_integer;
    for(int numero=0; numero < 5000; numero++){
    random_integer = 0 + int(6 * rand()/(RAND_MAX+1.0));
    cout << random_integer << endl;
}
    cin.get();
    return 0;
}

I realize that it is currently printing out only the random numbers...

Last edited by Armfelt; Apr 21st, 2007 at 1:20 pm.

•

Join Date: Jun 2006

Posts: 7,616

Reputation: ~s.o.s~ has much to be proud of

Solved Threads: 466

~s.o.s~

Offline

Failure as a human

Re: Counting the frequency of random numbers

Apr 21st, 2007

You would be required to have an array of the size the same as the range of numbers to be generated. For eg. as in your case, the range is 5, hence create an array of 5 elements, and for each random number generated, do something like:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
int frequencyArray [RANGE] = { 0 };
random_integer = int(6 * rand()/(RAND_MAX+1.0));
 
// asssuming that the generated number is between 1 and 5.
++frequencyArray [randomNumber - 1];
int frequencyArray [RANGE] = { 0 };
random_integer = int(6 * rand()/(RAND_MAX+1.0));

// asssuming that the generated number is between 1 and 5.
++frequencyArray [randomNumber - 1];

BTW, why the need to add zero to your random number equation, which I think would also generate 0 which you don't need.

Consider doing:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
srand ( static_cast<unsigned int> ( time ( 0 ) ) );
random_integer = 1 + int(5 * rand()/(RAND_MAX+1.0));
srand ( static_cast<unsigned int> ( time ( 0 ) ) );
random_integer = 1 + int(5 * rand()/(RAND_MAX+1.0));

Last edited by ~s.o.s~; Apr 21st, 2007 at 1:30 pm.

I don't accept change; I don't deserve to live.

•

Join Date: Apr 2007

Posts: 4

Reputation: Armfelt is an unknown quantity at this point

Solved Threads: 0

Armfelt

Offline

Newbie Poster

Re: Counting the frequency of random numbers

Apr 21st, 2007

I managed to figure it out. The code is sans Arrays due to the realization that I am not supposed to know how to use them yet. Sincere thanks for the help ~s.o.s~. For posterity, here is the code:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <vcl>
#include <iostream>
#include <ctime>
 
using namespace std;
 
int main(void)
{
srand((unsigned)time(0));
int random_integer;
int number1 = 0;
int number2 = 0;
int number3 = 0;
int number4 = 0;
int number5 = 0;
int lowest=1, highest=5;
int size=(highest-lowest)+1;
 
for(int n=0; n < 5000; n++)
{
random_integer = alin+int(koko*rand()/(RAND_MAX+ 1.0));
 cout << random_integer << endl;
  if (random_integer == 1) numero1++;
   else if (random_integer == 2) numero2++;
    else if (random_integer == 3) numero3++;
     else if (random_integer == 4) numero4++;
      else if (random_integer == 5) numero5++;
}
cout << random_integer << endl;
cout << "\n1 = "<<number1<<""<<endl;
cout << "2 = "<<number2<<""<<endl;
cout << "3 = "<<number3<<""<<endl;
cout << "4 = "<<number4<<""<<endl;
cout << "5 = "<<number5<<""<<endl;
 
cin.get();
return 0;
}
#include <vcl>
#include <iostream>
#include <ctime>

using namespace std;

int main(void)
{
srand((unsigned)time(0));
int random_integer;
int number1 = 0;
int number2 = 0;
int number3 = 0;
int number4 = 0;
int number5 = 0;
int lowest=1, highest=5;
int size=(highest-lowest)+1;

for(int n=0; n < 5000; n++)
{
random_integer = alin+int(koko*rand()/(RAND_MAX+ 1.0));
 cout << random_integer << endl;
  if (random_integer == 1) numero1++;
   else if (random_integer == 2) numero2++;
    else if (random_integer == 3) numero3++;
     else if (random_integer == 4) numero4++;
      else if (random_integer == 5) numero5++;
}
cout << random_integer << endl;
cout << "\n1 = "<<number1<<""<<endl;
cout << "2 = "<<number2<<""<<endl;
cout << "3 = "<<number3<<""<<endl;
cout << "4 = "<<number4<<""<<endl;
cout << "5 = "<<number5<<""<<endl;

cin.get();
return 0;
}

I presume that the the aesthetics of my code do not appeal to patrons

Last edited by Armfelt; Apr 21st, 2007 at 3:11 pm. Reason: code indenting enhancements & minor tweaks..

•

Join Date: Aug 2005

Posts: 5,266

Reputation: iamthwee is a splendid one to behold

Solved Threads: 377

iamthwee

Offline

Posting Expert

Re: Counting the frequency of random numbers

Apr 21st, 2007

>I presume that the the aesthetics of my code do not appeal to patrons

No but your avatar does

>#include <iostream.h>
No it should be just iostream.

Don't forget to align your braces and properly indent your code.

*Voted best profile in the world*

•

Join Date: Apr 2007

Posts: 4

Reputation: Armfelt is an unknown quantity at this point

Solved Threads: 0

Armfelt

Offline

Newbie Poster

Re: Counting the frequency of random numbers

Apr 21st, 2007

Thanks for the pointers (and praise for my avatar

) I edited the code accordingly.

•

Join Date: Aug 2005

Posts: 5,266

Reputation: iamthwee is a splendid one to behold

Solved Threads: 377

iamthwee

Offline

Posting Expert

Re: Counting the frequency of random numbers

Apr 21st, 2007

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <vcl>
#include <iostream>
#include <ctime>
 
using namespace std;
 
int main ( void )
{
   srand ( ( unsigned ) time ( 0 ) );
   int random_integer;
   int number1 = 0;
   int number2 = 0;
   int number3 = 0;
   int number4 = 0;
   int number5 = 0;
   int lowest = 1, highest = 5;
   int size = ( highest - lowest ) + 1;
 
   for ( int n = 0;  n < 5000;  n++ )
   {
      random_integer = alin + int ( koko * rand() / ( RAND_MAX + 1.0 ) );
      cout << random_integer << endl;
      if ( random_integer == 1 ) 
          numero1++;
      else if ( random_integer == 2 ) 
          numero2++;
      else if ( random_integer == 3 ) 
          numero3++;
      else if ( random_integer == 4 ) 
         numero4++;
      else if ( random_integer == 5 ) 
         numero5++;
   }
   cout << random_integer << endl;
   cout << "\n1 = " << number1 << "" << endl;
   cout << "2 = " << number2 << "" << endl;
   cout << "3 = " << number3 << "" << endl;
   cout << "4 = " << number4 << "" << endl;
   cout << "5 = " << number5 << "" << endl;
 
   cin.get();
   return 0;
}
#include <vcl>
#include <iostream>
#include <ctime>

using namespace std;

int main ( void )
{
   srand ( ( unsigned ) time ( 0 ) );
   int random_integer;
   int number1 = 0;
   int number2 = 0;
   int number3 = 0;
   int number4 = 0;
   int number5 = 0;
   int lowest = 1, highest = 5;
   int size = ( highest - lowest ) + 1;

   for ( int n = 0;  n < 5000;  n++ )
   {
      random_integer = alin + int ( koko * rand() / ( RAND_MAX + 1.0 ) );
      cout << random_integer << endl;
      if ( random_integer == 1 ) 
          numero1++;
      else if ( random_integer == 2 ) 
          numero2++;
      else if ( random_integer == 3 ) 
          numero3++;
      else if ( random_integer == 4 ) 
         numero4++;
      else if ( random_integer == 5 ) 
         numero5++;
   }
   cout << random_integer << endl;
   cout << "\n1 = " << number1 << "" << endl;
   cout << "2 = " << number2 << "" << endl;
   cout << "3 = " << number3 << "" << endl;
   cout << "4 = " << number4 << "" << endl;
   cout << "5 = " << number5 << "" << endl;

   cin.get();
   return 0;
}

Well I might be tempted to do something like the above.

Also does cout << "\n1 = " << number1 << "" << endl; have any purpose?

*Voted best profile in the world*

•

Join Date: Apr 2007

Posts: 4

Reputation: Armfelt is an unknown quantity at this point

Solved Threads: 0

Armfelt

Offline

Newbie Poster

Re: Counting the frequency of random numbers

Apr 21st, 2007

•

Also does cout << "\n1 = " << number1 << "" << endl; have any purpose?

That bit was left over from an a planned text output thingy. Good catch.

Let me guess: you ran the code through a 'beautifier' program of some sort? Or did you blaze through it pressing space

. I must agree it looks better that way. Case closed!