programming-for-dummies

594
Declaring Variables
Table 5-2 (continued)
Data Type Number of Bytes Range
Uint16 2 0 to 65535
Uint32 4 0 to 4,294,967,295
Uint64 8 0 to 2^64–1
Declaring decimal data types
Decimal values represent numbers such as 1.28 or –90.4. Just as you can
limit the range of integer values a variable can hold, so can you limit the
range of decimal values a variable can hold. In Visual Basic, the three types
of decimal data types are Single, Double, and Decimal (as shown in Table
5-3). In REALbasic, the only two decimal data types are Single and Double
(as shown in Table 5-4).
Table 5-3
Visual Basic Decimal Data Types
Data Type Number of Bytes Range
Single 4 –3.402823 E38 to –1.401298 E-45
(negative values)
1.401298 E–45 to 3.402823 E38
(positive values)
Double 8 –1.79769313486231 E308 to
–4.94065645841247 E–324
(negative values)
4.94065645841247 E–324 to
1.79769313486232 E308
(positive values)
Decimal 12 +/–79,228,162,514,264,337,593,
543,950,335 (no decimal point)
+/–7.9228162514264337593543950335
(up to 28 decimal places)
Table 5-4
REALbasic Decimal Data Types
Data Type Number of Bytes Range
Single 4 1.175494 E–38 and 3.402823 E+38
Double 8 2.2250738585072013 E–308 and
1.7976931348623157 E+308
To declare a variable as a Decimal data type, use the Single, Double, or
Decimal keyword, such as
Dim TaxRefund As Single