Double Data Type (Visual Basic)
Holds signed IEEE 64-bit (8-byte) double-precision floating-point numbers ranging in value from -1.79769313486231570E+308 through -4.94065645841246544E-324 for negative values and from 4.94065645841246544E-324 through 1.79769313486231570E+308 for positive values. Double-precision numbers store an approximation of a real number.
Remarks
The Double data type provides the greatest and smallest possible magnitudes for a number.
The default value of Double is 0.
Programming Tips
Precision. When you work with floating-point numbers, keep in mind that they do not always have a precise representation in memory. This could lead to unexpected results from certain operations, such as value comparison and the Mod operator. For more information, see Troubleshooting Data Types.
Trailing Zeros. The floating-point data types do not have any internal representation of trailing 0 characters. For example, they do not distinguish between 4.2000 and 4.2. Consequently, trailing 0 characters do not appear when you display or print floating-point values.
Type Characters. Appending the literal type character R to a literal forces it to the Double data type. Appending the identifier type character # to any identifier forces it to Double.
Framework Type. The corresponding type in the .NET Framework is the System.Double structure.
See Also
Tasks
Reference
Data Type Summary (Visual Basic)
Decimal Data Type (Visual Basic)
Single Data Type (Visual Basic)
Type Conversion Functions
Conversion Summary
System.Double