Invalid conversion from 'int' to 'double*'

Question

I have this line of code:

int g = modf(ans*power, 1)*10;

And it is giving me the error:

Invalid conversion from \'int\'

Answer 1

modf expects a pointer to a double as its second argument. See here.

Answer 2

modf(ans*power, 1) is bad

double smthng = 1.0; modf(ans*power, &smthng) is good.

http://linux.die.net/man/3/modf

Answer 3

modf(double x, double * intpart);
                     ^^^

See modf

Answer 4

I don't see where I am using a pointer : you're not, and that is the problem. Look at the signature of modf:

double modf( double, double* );

It requires a double* as second argument; you're passing it an int.