Thread: C - float and double data-type question..

hi again every1, can any1 please help me with this one? thanks.. ^.^

..i made a c program that should output the square root of a number....

Code:

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

int main()
{
	double x=100;

	clrscr();

	printf("Square root of 100 is equals to: %lf", sqrt(x));

	getchar();

	return 0;
}

...but every time it does, in this example, it shows 10.000000 (..which is the square root of 100..)

what i want is to make the program output 10 (..with no decimals..) instead of 10.000000...




...another program i made that uses the pow() function:

Code:

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

int main()
{
	double x=10;

	clrscr();

	printf("10 raised to 2 is equals to: %lf", pow(x, 2));

	getchar();

	return 0;
}

...also has the same problem, it shows 100.000000 instead of just 100





....about the float and double data-type, is it correct that the %lf parameter in the printf() function is for double, and %f for float? im just confused... thanks again for your help and advise... ^.^

...and uhmmm btw, about the title for this post i made, if you found it inappropriate, please, accept my apologies...

The only thing u have to change is to declare x as an int instead of double(and also in printf %d instead of %lf).double & float gives u the output in real form not in integer form.
also %lf is used for double and %f for float.

Originally Posted by ShadeS_07

what i want is to make the program output 10 (..with no decimals..) instead of 10.000000...

Have you tried:

printf("Square root of 100 is equals to: %2.0f", sqrt(x));

?

And don't forget about the %g format specifier, which also trims trailing zeroes automatically. (It also will change from "normal" format to "exponential" format automatically too.)

printf("Square root of 100 is equals to: %d", sqrt(x));
gives output as 0, however
printf("Square root of 100 is equals to: %d", (int)sqrt(x));
gives the correct output of 10.
I wonder why the first doesn't work.

ah. that explains it. thanks a lot.

thankyou so much for all your help and advise, i really appreciate it... ^.^


..uhmm, one more question please... what does %2.0f do? what does it mean? thnkz... ^.^

Originally Posted by Mole42

Have you tried:

printf("Square root of 100 is equals to: %2.0f", sqrt(x));

?