Stacked Lines Window
The stacked line plot window allows you to plot one or more ordinate (Y)
quantities against a monotonic abscissa (X) quantity.
For clarity, the different plots are displayed on vertically
displaced graphs which share the same X axis.
You can display this window using the Lines ()
button in the Control Window's toolbar.
The display initially holds a single X-Y graph, usually with lines connecting adjacent points. The points will be reordered before drawing if necessary so that the line is displayed as a function of X, rather than of an invisible third independent variable (in the Scatter Plot this isn't done which can lead to lines being scribbled all over the plot). If one of the columns in the table appears to represent a time value, this will be selected as the default X axis. Otherwise, the 'magic' index variable will be used, which represents the row number. Of course, these can be changed from their default values using the selectors in the usual way.
To add a new graph with a different Y axis, use the
Add Dataset () button in the
dataset selectors panel at the bottom
of the window.
This has a slightly different effect from what it does in the other
plot windows, in that it inserts a new plotting region with its own
Y axis at the top of the plot on which the specified data is drawn,
rather than only causing a new set of points to be plotted on the
existing plot region.
Thus all the datasets appear in their own graphs with their own Y axes
(though if you have multiple row subsets plotted for the same
dataset they will appear on the same part of the plot as usual).
To remove one of the graphs, select its tab and use the
Remove Dataset (
) button as usual.
Zooming can only be done on one axis at a time
rather than dragging out an X-Y region on the plot surface, since
there isn't a single Y axis to zoom on.
To zoom the X axis in/out, position the mouse just below the X axis
at the bottom of the plot and drag right/left.
To zoom one of the Y axes in or out, position the mouse just to the
left of the Y axis you're interested in and drag down/up.
To set the ranges manually, use the Configure Axes
() button as usual, but note that there is one
label/range setting box for each of the Y axes.
These things work largely as described in Appendix A.4.1.2,
as long as you bear in mind that the range of each of the Y axes
is treated independently of the others.
Clicking on any of the points will activate it - see Section 7.
The following buttons are available on the toolbar:
You can determine how the data are plotted using lines and/or markers as described in the following subsection.