Double-precision floating-point (#)

Double-precision floating-point numbers are to Single-precision numbers what Long-integers are to Integers.  They take twice as much space in memory (8 bytes versus 4 bytes), but have a greater range (+/- 4.19*10^-307 to 1.79*10^308) and a greater accuracy (15 to 16 digits of precision versus the 6 digits of Single-precision).  A Double-precision, 5,000-element array requires 40,000 bytes.  An Integer array with the same number of elements occupies only 10,000 bytes.  The type-specifier character for a Double-precision floating-point is: #.

Double-precision variables are identified by following the variable name with a Number symbol (i.e., var#) or by using the DEFDBL statement as described in the previous discussion of Integers.  You can also declare Double-precision variables using the DOUBLE keyword with the DIM statement.  For example:


C/C++, Delphi, and Visual Basic all offer a double data type that is identical to the PowerBASIC Double-precision variable.


See Also

Array Data Types

Bit Data Types

Constants and Literals

Floating Point Data Types 

GUID Data Types

Integral Data Types 

Object Data Types


String Data Types 

User Defined Types


Variant Data Types