Is it better to write 0.0, 0.0f or .0f instead of simple 0 for supposed float or double values

Question

Hello well all is in the title. The question apply especially for all those values that can be like NSTimeInterval, CGFloat or any other variable that is a float or a double. Thanks.

EDIT: I'm asking for value assignment not format in a string.

EDIT 2: The question is really does assigning a plain 0 for a float or a double is worst than anything with f a the end.

Answer 1

The basic difference is as :

1.0 or 1. is a double constant

1.0f is a float constant

Without a suffix, a literal with a decimal in it (123.0) will be treated as a double-precision floating-point number. If you assign or pass that to a single-precision variable or parameter, the compiler will (should) issue a warning. Appending f tells the compiler you want the literal to be treated as a single-precision floating-point number.

Answer 2

If you are initializing a variable then it make no sense. compiler does all the cast for you.

float a = 0; //Cast int 0 to float 0.0
float b = 0.0; //Cast 0.0 double to float 0.0 as by default floating point constants are double
float c = 0.0f // Assigning float to float. .0f is same as 0.0f

But if you are using these in an expression then that make a lot of sense.

6/5 becomes 1
6/5.0 becomes 1.2 (double value)
6/5.0f becomes 1.2 (float value)