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The double data type defines an IEEE-754 floating-point number. It is used as follows:

double name <[>= value<]>;


name is the name of the variable.
value is the value to assign to the variable.


  • The double data type is identical to the float data type. Variables of type double are implemented using the same 4-byte storage format as float types.

Refer to Floating-point Numbers for information regarding the format of double types.

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