Linux Manual Pages

Free Software * Books

Source Code

Free Media

Linux

Tcl_DoubleObj

NAME
SYNOPSIS
ARGUMENTS
DESCRIPTION
SEE ALSO
KEYWORDS

___________________________

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.

______________

DESCRIPTION

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

KEYWORDS

double, double object, double type, internal representation, object, object type, string representation

Opportunity

Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.

Free Software

Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.

Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.

Free Books

The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.

Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.

Education

Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.

Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.