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Double Field Type

When you need more accuracy, for example, when you have a fixed amount of storage in your table or true floating-point values, use the Double data type instead of Numeric. Unlike with numeric data, you determine the position of the decimal point when you enter the value in a table.

Note

When the Double data type is used in a table, the number of decimals specified when the field is created is for display purposes only. Visual FoxPro stores the actual value in the field.

For specifications about the Double field type, see Visual FoxPro Data and Field Types.

Example

The following example creates a cursor with a Double field and specifies 2 digits of precision for the field. The field displays only 2 digits of precision even though the value contains more than 2 digits of precision.

&& Close any open databases and clear memory.
CLOSE DATABASES ALL 
CLEAR

&& Create a cursor with field of Double type.
CREATE CURSOR myCursor (myField B(2))

&& Insert value into cursor.
INSERT INTO myCursor VALUES (1234.561234)

&& Evaluate and display value in myField.
? EVALUATE("myCursor.myField") && Displays 1234.56.

&& Evaluate and compare values to determine actual value.
? EVALUATE("myCursor.myField") = 1234.56 && Displays .F.
? EVALUATE("myCursor.myField") = 1234.561234 && Displays .T.

See Also

Tasks

How to: Choose Data Types

Concepts

Creating Numeric Expressions

Reference

Numeric Operators

CREATE CURSOR - SQL Command

INSERT - SQL Command

EVALUATE( ) Function

Other Resources

Data and Field Types