Floating point literals specify values that must have a fractional part. These values contain decimal points (.) and can contain exponents. There are two floating point literals in ATEasy:
Float (for example, 3.56f, -3.4E-38f)
Double (for example, 3.56 or 3.56d)
The following table summarizes these two types of floating point literals:
|
Type |
Value range |
Magnitude range |
Suffix |
Examples |
|
Float |
3.4E +/- 38 (7 digits) |
Magnitude range of +/- 1.2E -038. |
f |
3.56f, -3.4E-38f, or 3.f |
|
Double |
1.7E +/- 308 (15 digits) |
Magnitude range of +/- 2.3E -308. |
optional letter 'd' |
1.7E+308, 3.56d, 3.56, or 3. |
mantissa [optional exponent] suffix
The syntax has the following parts:
|
Name |
Components |
Description |
|
mantissa |
A sequence of numeral digits (0-9), plus a period, plus an optional series of numeral digits(0-9). |
The value of the number. If the value is positive, the plus sign is optional. |
|
exponent |
The character e or E (either case may be used), plus a positive or negative numeral (0-9). |
The magnitude of the number as a power of 10. If the magnitude is positive, the plus sign is optional. |
|
suffix |
This can be f for a Float or d for a Double. |
A character specifying the type of float literal constant. The suffix d is optional for the Double floating point literal. |
The exponent, if present, specifies the magnitude of the number as a power of 10, as shown in the following example:
18.46e0 ! is the same as 18.46
18.46e1 ! is the same as 184.6
If an exponent is present, the trailing decimal point is unnecessary in whole numbers such as 18E0.
Floating-point constants default to type double. By using the suffixes f or l, the constant can be specified as float or double, respectively.