C Programming Language

Floating-point constants

                 A floating-point constant is a base-10 number that contains either a decimal point or an exponent or both. A floating-point constant can be written in two forms: Factorial form or Exponential form. A floating-point constant in a fractional form must have at least one digit each to the left and right of the decimal point. A floating-point in exponent form consists of a mantissa and an exponent. The mantissa itself is represented as a decimal integer constant or a decimal floating-point constant in fractional form. The letter E or e and the exponent follow the mantissa. The exponent must be a decimal integer. The actual number of digits in the mantissa and the exponent depends on the computer being used.

The following are valid floating-point constants.</1.0             0.1           2E-4    -0.1555e-4

The following floating-point constants are written incorrectly for the reasons stated.written incorrectly for the reasons stated.

                       1                       No decimal point or exponent.
                  2,00.8                  Illegal character (,).
                      2                        E+10.20 Exponent must be an integer.
                      3                        E10 Illegal character (space).  

Example:

Integer constants Home Character constants

c program stats