SETPREC()
 Sets the precision level for trigonometric functions
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 Syntax

     SETPREC(<nPrecision>) --> cNull

 Argument

     <nPrecision>  Designates the number of places for computational
     precision in the range of 1 to 16.  The default value is 16.

 Returns

     SETPREC() always returns a null string.

 Description

     SET PRECISION
     CA-Clipper Tools works with the default precision set at 16 places to
     the right of the decimal for trigonometric functions.  If you do not
     want this precision level, or you want a faster execution speed, reduce
     the number of places accordingly.  The following functions are affected:

     SIN()  COS()  TAN()  COT()  ASIN()  ACOS()  ATAN()  ATN2()

 Example

     Set a precision level of 10 places:

     SETPREC(10)         // Always returns a null string