Getting started

Here the basic steps to generate a simple picture are described.
It is assumed that gd is properly installed on your system.

1. Prepare a data file

   Pickup your favorite text editor and create a data file.
   It may look like:

   'Fission barriers of Ac isotopes'
   X: neutron number
   Y: Bf$ / MeV
   H: X   Y1(droplet),D13  Y2(total),L11
    124      6.60           11.11
    126      6.57           11.94
    128      6.51           10.36
    130      6.42            9.18
    132      6.32            8.42
   H: Y(exp),N6   D+    D-     X
       8.5       1    1.5    128
   W:Ac/ X(129) Y(11) S(20) A(0)

   It consists of a header line written above the graph (1st line),
   text for the x- and y-axis (X:- and Y:- tags),
   two data blocks (starting with the H:-tags)
   and an extra text line (W:).
   The data blocks themselves comprise a column of x-values as well as
   several columns of y-values and y-errors.
   Save the data file as, say,

2. Start the gd program

   Select a shell window and type

   gd new

   to invoke the latest installed version.
   A prompt (Enter Command :) appears indicating that the program is ready
   to accept your commands.

3. Read the data

   You use the gd command GREAD to read the data file just edited.
   Just type


   and the data will be read into memory.

4. Display the data

   You use the gd command GDISP to read the data file just edited.
   Just type


   and the graph will appear on the default graphics screen.
   The default representation is determined automatically but can be changed by
   specifying additional display parameters.

5. Make a paper copy

   You use the gd command GCOPY to create a copy on paper.
   There are several options you might choose:

   gcopy printerqueue

   will generate an immediate picture on the specified PostScript printer queue.


   will create a PostScript file with the specified name.
   This file can be printed later or included in a text processing program.

6. Leave the session

   You use the gd commands GEXIT or EXIT to exit the program.