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Tcl_DoubleObj(3)                           Tcl Library Procedures                           Tcl_DoubleObj(3)



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NAME
       Tcl_NewDoubleObj,  Tcl_SetDoubleObj,  Tcl_GetDoubleFromObj - manipulate Tcl objects 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 object.

       Tcl_Obj *objPtr (in/out)             For  Tcl_SetDoubleObj,  this  points  to  the object in which to
                                            store a double value.  For Tcl_GetDoubleFromObj, this refers  to
                                            the object 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 objects that hold double-precision float-ing-point floating-point
       ing-point values.

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

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

       Tcl_GetDoubleFromObj  attempts to retrieve a double value from the Tcl object objPtr.  If the attempt
       succeeds, then TCL_OK is returned, and the double value is written to the storage pointed to by  dou-blePtr. doublePtr.
       blePtr.   If  the attempt fails, then TCL_ERROR is returned, and if interp is non-NULL, an error mes-sage message
       sage 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 object, double type, internal representation, object, object type, string representa-tion representation
       tion



Tcl                                                  8.0                                    Tcl_DoubleObj(3)