Thread: How to connect C with MySql

Make it like this.

Code:

 
  // Enter the value of Radius for calculation of above.
  printf("Please enter the value of circle radius \n");
  scanf("%f", &radius);

  // These are the lines that need to move.
  diameter = radius * 2;
  circumference = diameter * pie;
  radius = diameter / 2;
  pie = circumference / diameter;  // before area
  area = radius * pie * radius;

Originally Posted by mba_110

Not clear you are telling it in a very limited words, move what from what ? input data from what those calculations ?

Not clear to understand anything, please write in details what actually required to do.

here i want all values of pie,diameter,circumference and area based on radius i have provided, so once i input radius it should show four separate lines showing for category result.

C doesn't allow code like this

Code:

area = width * height;
height = 4;
width = 5;
// expect area to be 20

There is no way of setting up an equation then expecting the result to be adjusted when the right hand side is set.

However if you do this

Code:

height = 4;
width = 5;
area = width * height;
// area is now 20

it will work as you would expect.

Originally Posted by Salem

Make it like this.

Code:

 
  // Enter the value of Radius for calculation of above.
  printf("Please enter the value of circle radius \n");
  scanf("%f", &radius);

  // These are the lines that need to move.
  diameter = radius * 2;
  circumference = diameter * pie;
  radius = diameter / 2;
  pie = circumference / diameter;  // before area
  area = radius * pie * radius;

I am not getting the result all are zero nothing is showing.

Code:

#include <stdio.h>#include <stdlib.h>

int main()
{                               //Program to find area, circumference and diameter of circle based on Radius.


  //Data types
  float diameter;
  float circumference;
  float radius;
  float area;
  float pie;

  //Enter the value of Radius for calculation of above.
  printf("Please enter the value of circle radius \n");
  scanf("%f", &radius);

  // Variable declaration for calculation
  diameter = radius * 2;
  circumference = diameter * pie;
  radius = diameter / 2;
  pie = circumference / diameter;
  area = radius * pie * radius;


  // Calculation of Pie
  printf("The Pie of Circle is %f\n", pie);
  //scanf("%f",&pie);

  // Calculation of Circle's Area.
  printf("The circle area is %f\n", area);
  //scanf("%f",&area);

  // Calculation of Circumference of Circle.
  printf("The Circumference of Circle is %f\n", circumference);
  //scanf("%f",&circumference);

  // Calculation of Diameter of Circle.
  printf("The Diameter of Circle is %f\n", diameter);
  //scanf("%f",&diameter);

  return 0;
}

For future reference, please use "copy as text" in your code editor, and/or "paste as text" in your browser.
The colour/font ridden mess isn't sustainable.

circumference = diameter * pie;
pie = circumference / diameter;

You're going round in circles here!

Originally Posted by Kernelpanic

Of course, because your variable declaration doesn't make sense.

circumference = diameter * pie; - is what?

If diameter is 2 times radius, 2 times PI times r is the same as PI times diameter!

And your code uses unecessary headers. Take a look at this simplification:

Code:

// circ.c
//
// Compile with:
//    gcc -O2 -o circ circ.c
//
// NOTE: Don't need to link with libm.
//

#include <stdio.h>
#include <stdlib.h>   // nedded only for EXIT_FAILURE, EXIT_SUCCESS constants.
                      // if you use 1 and 0 as return values, stdlib.h isn't necessary.
#include <math.h>     // needed only for M_PI constant, otherwise, not needed.

// FIX: Notice using "%lf" conversion is WRONG, except in scanf().
int main( void )
{
  double d, p, r, a;

  // Since stdout is LINE BUFFERED, you should call fflush().
  printf( "Please enter the value of circle radius in cm: " );
  fflush( stdout );

  // NOTE: You should check if scanf() was abble to do the
  //       conversion.
  if ( scanf( "%lf", &r ) != 1 )
  {
  error:
    fputs( "ERROR: Invalid value.\n", stderr );
    return EXIT_FAILURE;
  }

  if ( r < 0.0 )
    goto error;

  // NOTE: math.h defines M_PI with double precision.
  //       Don't need to call pow() from libm!
  d = r + r;          // 2r = r+r
  p = M_PI * d;       // 2πr == πd
  a = M_PI * r * r;   // πr² = πrr

  // NOTE: Here %lf is WRONG. To use 'long double' it should be %Lf (uppercase L),
  //       But, we need only double.
  printf( "Diameter : %f cm\n"
          "Perimeter: %f cm\n" 
          "Area     : %f cm²\n",
          d, p, a );

  return EXIT_SUCCESS;
}

Originally Posted by flp1969

There is a M_PI constant in math.h. And you don't need stdlib.h.

Best to remember that M_PI is not standard, though

Question 14.8

Originally Posted by flp1969

// NOTE: Here %lf is WRONG. To use 'long double' it should be %Lf (uppercase L),

No, "Lf" is for long double and I don't use long. For double is "lf" correct.

Code:

#include <stdio.h>


int main(void)
{
   long double c = 42.0;
   double d = 42.0;   


   __mingw_printf("c = %Lf\n", c/3);  //Lf nur bei long double
   __mingw_printf("c = %lf\n", c/3);  //lf ist bei long double falsch (wrong)
   printf("d = %.4lf\n", d/3);             //Normal lf


   return 0;
}