5.3.7.2 Floating-point Constant

Floating-point constants have double type unless suffixed by f or F, in which case it is a float constant. The suffixes l or L specify a long double type which is considered an identical type to double by MPLAB XC8.

Floating point constants can be specified as decimal digits with a decimal point and/or an exponent. If you are using C99, they can be expressed as hexadecimal digits and a binary exponent, initiated with either p or P. For example:

myFloat = -123.98E12;
myFloat = 0xFFEp-22;  // C99 float representation