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Tcl_DoubleObj(3) Tcl Library Procedures Tcl_DoubleObj(3) ______________________________________________________________________________ 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 double object. Tcl_Obj *objPtr (in/out) For Tcl_SetDoubleObj, this points to the object to be converted to double type. For Tcl_GetDouble- FromObj, this refers to the object from which to get a double value; if objPtr does not already point to a double object, an attempt will be made to convert it to one. Tcl_Interp *interp (in/out) If an error occurs during conver- sion, an error message is left in the interpreter's result object unless interp is NULL. double *doublePtr (out) Points to place to store the dou- ble value obtained from objPtr. _________________________________________________________________ DESCRIPTION These procedures are used to create, modify, and read double Tcl objects from C code. Tcl_NewDoubleObj and Tcl_SetDoubleObj will create a new object of double type or modify an existing object to have double type. Both of these procedures set the object to have the double-pre- cision floating point value given by doubleValue; Tcl_NewDoubleObj returns a pointer to a newly created object with reference count zero. Both procedures set the object's type to be double and assign the dou- ble value to the object's internal representation doubleValue member. Tcl_SetDoubleObj invalidates any old string representation and, if the object is not already a double object, frees any old internal represen- tation. Tcl_GetDoubleFromObj attempts to return a double value from the Tcl object objPtr. If the object is not already a double object, it will attempt to convert it to one. If an error occurs during conversion, it returns TCL_ERROR and leaves an error message in the interpreter's result object unless interp is NULL. Otherwise, it returns TCL_OK and stores the double value in the address given by doublePtr. If the object is not already a double object, the conversion will free any old internal representation. SEE ALSO Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount, Tcl_GetObjResult KEYWORDS double, double object, double type, internal representation, object, object type, string representation Tcl 8.0 Tcl_DoubleObj(3)