Detect Decimal

[xniinja]

Hey guys I was wondering If it was possible to detect if a number is a decimal like this 5.5 but not an integer. Thanks for the help (sorry if you expecting a longer question )

[itsme86]

And how is this number stored? For example, if it's a string, it's pretty simple: if(strchr('.'))

[CommonTater]

There are several ways to do this...

For example you can use the abs() function...

float Num = 5.5;

if (abs(Num) != Num)
  puts"It is not a whole number";

[nonoob]

abs() ?

Perhaps floor().

[CommonTater]

abs() ?

Perhaps floor().

You're right... my bad.

[xniinja]

Thanks for the help, I have started with my programming, it will do synthetic division, but I have ran into a slight problem. To be honest I don't know what is happening but I know its in the while loop and when I step through the program on my debugger it just quits when it gets to the while loop. Here is my code...

#include <stdio.h>
#include <math.h>

main()
{
      double test;
      
      int c;
      
      int a;
      
      int divide = 0;
      
      double cdivide;
      
      double pmax;
      
      test = 5.5;
      
      printf("enter c:");
      
      scanf("%d",&c);
      
      printf("\nnow enter a:");
      
      scanf("%d",&a);
      
      pmax = 2 / c;

      while(divide <= pmax)
      {
                 cdivide = c / divide;

      if( floor(cdivide) != cdivide)
      {
          printf("not an int");
          
      }
      else
      {
          printf("new p found: %d",cdivide);
      
      }
      divide++;
      }
      printf("done");
      getch();
      return 0;
}

thanks again

[quzah]

if( (float)((int) f) != f )
    print( "Houston, we have a decimal.\n" );

Quzah.

[Bayint Naung]

modf(3) - Linux man page
No worry about overflow.

[CommonTater]

     while(divide <= pmax)
      {
                 cdivide = c / divide;

Take a close look at your code... what is the value of the divide variable when it gets to the bit above?