Hi,

Can anyone help me to find the power of a number without using pow function in C. For eg., 2.5 raised to the power of 1.5.

Thanks.

If it's an integer, I can help. But raising to the power of a floating point number? No idea!

for integers this should work:

int powi(int number, int exponent)
{
	int i, product = 1;
	for (i = 0; i < exponent; i++)
		product *= number;

	return product;
}

for floats, well i don't have time now to test it but i guess this should work:

double powf(float base, float exponent)
{
	return exp(log(base) * exponent);
}

oh and if log(x) doesn't produce what u need, try log10(x).

Thanks for sharing. Didn't feel that the use of the log finction would be allowed.

no problem. i didn't think log was allowed but i didnt see any other way of solving it except some taylor series expansion wahala.

double powf(float base, float exponent)

Shudnt that be

float powf(float base, float exponent)

The return val cud be a floating point stuff now, cant it?

exp() returns a double.

The easiest way to do it is to call a built in calculator with the expression of ur choixe, or an online calculator, for example,

http://www.google.com/search?q=5^6

will give you a google page with the answer or 5^6,

In c, you can call a get on any website of your choice, eg, http://www.google.com/search?q=5^6, and 'get' will give you all the text derived from the query, you can then use 'sed' to search the expression for the answer to your question, say if u need sample code doing this,

Sori guyz plz dont crucify me coz am kinda new to c programming,and am even learning it maself.but i was wondering why u couldnt use the exponentation (^) operator.i guess it shuld work.

This show work. main() { float a=2.15,b=1.5; power(&a,&b);} void power(float *x,*y) { float i=1.0,val=1.0; while(i++<=*y) val=val * *x; printf(" %f the power of %f is %f",*x,*y,val);

We can find the power of a number without using pow function and using recursion.
Let power(a, b) means ab.
If b is even : power(a, b) = power(a, b/2)*power(a, b/2);
if b is odd : power(a, b) = power(a, b/2)*power(a, b/2)*a;
For example:
28 = 24 * 24;
29 = 24 * 24 * 2;
Source : http://www.techcrashcourse.com/2014/10/c-program-calculate-power-of-number.html