Random Number Generator Counts

[Jaxtomtom89]

// functon genRandom receives the four parameters to use for the pseud-random
// number generator.  It generates the numbers, prints them, and calls 
// the subfunction addToCounts for specific counts.
void genRandom(int aSeed, int aLb, int aUb, int aNumToGen,
               int* pEven, int* pOdd, int* pNeg, int* pPos, int* pZero )
{
   // Local Declarations for srand
   int range = (aUb - aLb) + 1;
   int lineCount = 0;
   int randNum;
   srand(aSeed);
   // Local declaractions initialized for use in addToCounts
   *pEven = 0;
   *pOdd = 0;
   *pNeg = 0;
   *pPos = 0;
   *pZero = 0;
   
   // starts format for ouputs
   printf("\nNumbers generated:\n");
   
   // while loop used to obtain quanitity of randoms.  Per each iteration,
   // addToCounts is called to specify the type of each number generated.
   while (aNumToGen > 0){
      if (lineCount < 10)
         lineCount++;
      else{
         printf("\n");
         lineCount = 1;
         }
      printf("%4d", rand() % range + aLb);
      randNum = rand() % range + aLb;
      aNumToGen--;
      addToCounts(randNum, pEven, pOdd, pNeg, pPos, pZero);
      }
      
                 

}
// function addToCounts receives the pseudo-random numbers and counts the 
// number of evens, odds, negatives, positives, and zeroes that occur.
// It sends the counts back as output.
void addToCounts(int randNum, int* pEven, int* pOdd,
                 int* pNeg, int* pPos, int* pZero)
{
   
// if statements update the counts
   if (randNum % 2 == 0)
      (*pEven)++;
   if (randNum % 2 != 0)
      (*pOdd)++;
   if (randNum < 0)
      (*pNeg)++;
   if (randNum > 0)
      (*pPos)++;
   if (randNum == 0)
      (*pZero)++;
}

// printResults will display all the users inputs,the pseudorandom numbers
// generated and the counts all in aligned format
void printResults(int aSeed,int aLb, int aUb, int aNumToGen,
                  int aEven, int aOdd, int aNeg, int aPos, int aZero)
{

printf("\n\n");
printf("      Input Type                Value\n");
printf("     -----------           ----------\n");
printf("            Seed %20d \n", aSeed);
printf("     Lower Bound %20d \n", aLb);
printf("     Upper Bound %20d \n", aUb);
printf("Number Generated %20d \n", aNumToGen);

printf("\n\n");
printf("      Count Type                Value\n");
printf("    ------------                -----\n");
printf("           Evens %20d \n", aEven);
printf("            Odds %20d \n", aOdd);
printf("       Negatives %20d \n", aNeg);
printf("       Positives %20d \n", aPos);
printf("           Zeros %20d \n", aZero);
scanf("%d");
}

[msh]

0 is even. Hence, whenever randNum is 0, both *pEven and *pZero will be incremented.

[CommonTater]

// if statements update the counts
   if (randNum % 2 == 0)
      (*pEven)++;
   if (randNum % 2 != 0)
      (*pOdd)++;
   if (randNum < 0)
      (*pNeg)++;
   if (randNum > 0)
      (*pPos)++;
   if (randNum == 0)
      (*pZero)++;

This will work but there's no exclusivity... it is possible that more than one counter can be incremented at a time... It's also possible to simplify the testing somewhat... For example if randbum %2 == 0 it can't be !0 so you could use an else statement...

if (RandNum % 2 == 0)
  *peven++;
else
  *podd++;

You can add some exclusivity (if desired) like this...

if (RandNum == 0)
  *pzero++;
else
  { if (RandNum % 2 == 0)
           *peven++;
       else
           *podd++; }

You can use the same approach to the < zero and > zero tests as well.
One thing C does very well is complex conditionals...

[Jaxtomtom89]

To msh: Thank you for looking at it. I know it was a lot. The program is setup so that zero is counted as an even too. That's what our teacher wants. The problem is that counts are still off. Even when there is a zero in the numbers generated, it will show up as 0. All the counts just seem slightly off, but the conditions seem right to me at least.

To common Tater: I will play around with the conditionals and if statements as you say. Thank you much.

[msh]

And we have our winner!

printf("%4d", rand() % range + aLb);
randNum = rand() % range + aLb;

[Jaxtomtom89]

At msh: Thanks for looking at it again. I found it out as soon as I took a second look at the loop.

Swapped placements of randNum expression and printf, and set printf to print randNum instead.

[msh]

Good job.