NAME

       Tcl_NewDoubleObj,  Tcl_SetDoubleObj,  Tcl_GetDoubleFromObj  -  manipulate  Tcl  values  as
       floating-point values

SYNOPSIS

       #include <tcl.h>

       Tcl_Obj *
       Tcl_NewDoubleObj(doubleValue)

       Tcl_SetDoubleObj(objPtr, doubleValue)

       int
       Tcl_GetDoubleFromObj(interp, objPtr, doublePtr)

ARGUMENTS

       double doubleValue (in)              A  double-precision  floating-point  value  used   to
                                            initialize or set a Tcl value.

       Tcl_Obj *objPtr (in/out)             For  Tcl_SetDoubleObj,  this  points  to the value in
                                            which    to    store    a    double    value.     For
                                            Tcl_GetDoubleFromObj,  this  refers to the value from
                                            which to retrieve a double value.

       Tcl_Interp *interp (in/out)          When non-NULL, an error message  is  left  here  when
                                            double value retrieval fails.

       double *doublePtr (out)              Points  to  place  to store the double value obtained
                                            from objPtr.
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DESCRIPTION

       These procedures are used to create,  modify,  and  read  Tcl  values  that  hold  double-
       precision floating-point values.

       Tcl_NewDoubleObj  creates  and  returns  a  new  Tcl value initialized to the double value
       doubleValue.  The returned Tcl value is unshared.

       Tcl_SetDoubleObj sets the value of an existing Tcl value  pointed  to  by  objPtr  to  the
       double  value  doubleValue.  The objPtr argument must point to an unshared Tcl value.  Any
       attempt to set the value of a shared Tcl value violates Tcl's copy-on-write  policy.   Any
       existing  string  representation or internal representation in the unshared Tcl value will
       be freed as a consequence of setting the new value.

       Tcl_GetDoubleFromObj attempts to retrieve a double value from the Tcl  value  objPtr.   If
       the  attempt  succeeds,  then  TCL_OK  is returned, and the double value is written to the
       storage pointed to by doublePtr.  If the attempt fails, then TCL_ERROR is returned, and if
       interp  is non-NULL, an error message is left in interp.  The Tcl_ObjType of objPtr may be
       changed to make subsequent calls to Tcl_GetDoubleFromObj more efficient.

SEE ALSO

       Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount, Tcl_GetObjResult

KEYWORDS

       double, double value, double type, internal  representation,  value,  value  type,  string
       representation