To plot the data in the database tables you have
specified, select `PLOT` from the main option menu, enter the
parameter or expression that you want plotted on each axis. The main
plot menu lets you make various modifications to the retrieve request
and to the display of the data. Entering `;`

at this menu causes
the data to be retrieved and plotted.

<3=MO;> Plot,Regress,...? PL \* Options are: 1) Y < IP > 2) X < NE > 3) Constraints < > 4) Symbols < > 5) Graph ranges <Y: 0.0, 0.0, LIN> <X: 0.0, 0.0, LIN> Set? X X axis? IP Set? Y TE Set? ; Graph of TE vs IP RETURN

Figure 1 shows the graph of TE vs
IP. When you enter `RETURN`

, you go back to the main plot menu.
To graph TE vs IP but with fixed scales and symbols
distinguishing values of NE, you would do:

Set? G Y range and type 1. 4. Y (LIN or LOG) <LIN> , X range and type 300 500 X (LIN or LOG) <LIN> , Set? S Symbols? NE=2.5e19 NE=2.8e19 ; Set? ; Graph of TE vs IP

**Figure 2:** Rescaled scatter plot with symbol constraints

The graph is shown in Figure 2. At the bottom of
the graph, *LOCUS* displays the database, tables, today's date, a
sequence number, and the number of points retrieved. In parentheses,
the number of points that lie below or to the left of the graph and
the number of points that lie above or to the right of the graph are
shown--both zero in this case.

Commands are available after the graph has been drawn. Enter `?`

in the graphics window immediately after the graph is drawn to see a
complete list of commands which are described in
section 2.6. For example, to get a least squares
fit to the data points, enter `F`--the equation
of the fit, the correlation coefficient, and the variance are shown.
A least squares fit can be gotten for logarithmic plots as well as
linear. A polynomial fit can be gotten by entering the order of the
polynomial instead of `F`, or `0` can be used to get a
proportional fit. For more information about the fitting, see
section 2.6.1.

If you enter `RETURN`

at any of the axes or constraint prompts,
you can get a list of the parameters and names of expressions in the
tables you have selected:

X axis? RETURN Table TESCAL IP NE SHOT TE Expressions from XTESCAL IP_MAX IP_ROUND TAUE TAUE_MS

Fri Jul 11 17:05:56 EDT 1997