## DESCRIPTION

           BLT is a library of extensions to the Tk library.  It adds new commands
           and variables to the application's interpreter.

## COMMANDS

           The following commands are  added  to  the  interpreter  from  the  BLT
           library:

           graph          A 2D plotting widget.  Plots two variable data in a win-
                          dow with an optional legend and annotations.   It has of
                          several  components; coordinate axes, crosshairs, a leg-
                          end, and a collection of elements and tags.

           barchart       A barchart widget.  Plots two-variable data as rectangu-
                          lar bars in a window.  The x-coordinate values designate
                          the position of the bar along the x-axis, while  the  y-
                          coordinate values designate the magnitude.  The barchart
                          widget  has  of  several  components;  coordinate  axes,
                          crosshairs,  a  legend, and a collection of elements and
                          tags.

           vector         Creates a vector of floating point values.  The vector's
                          components  can  be manipulated in three ways: through a
                          Tcl array variable, a Tcl command, or the C API.

## ADDING BLT TO YOUR APPLICATIONS

           It's easy to add BLT to an existing Tk application.   BLT  requires  no
           patches  or  edits  to the Tcl or Tk libraries.  To add BLT, simply add
           the following code snippet to your application's tkAppInit.c file.

           if (Tkblt_Init(interp) != TCL_OK) {

               return TCL_ERROR;

           }

           Recompile and link with the tkblt library and that's it.

           Alternately, you can dynamically load tkblt,  simply  by  invoking  the
           command

           % package require tkblt

           from your Tcl script.

## BUGS

           Send bug reports, requests, suggestions, etc. to wjoye@cfa.harvard.edu

## KEYWORDS

           BLT