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A.5.2 Window Overview

Layer plot window

Layer plot window

Layer plot windows consist of two main parts: at the top is the plot itself, and at the bottom is the control panel. The control panel is where you configure what will be plotted. For a simple scatter plot it may just be a case of selecting what columns to plot against each other, but it can get quite detailed. If you want more screen space to play with, it can be helpful to float the control panel into a separate window using the Float Controls () toolbar button. To unfloat the control panel, either just close the control panel window, or click the Float Controls toolbar button again. With floating controls, the window looks like the following figure.

Layer plot window with floated control panel

Layer plot window with floated control panel

The control panel itself has two parts: a list on the left of currently active controls (represented by names and icons), and a panel on the right which shows the currently selected control. Click on one of the control entries on the left to see its details on the right. Different controls have different detail panels, but in general each one will have multiple tabs for configuring different things. You can select these by clicking on the tab names. In general the best way to learn about the options is to click on the different controls and their tabs to see what's available and experiment with the various options to see what happens to the plot.

The control list has two types of entry:

Fixed controls:
These control the overall plot appearance. In the above figure, the fixed controls Axes () and Legend () are visible. The different fixed controls are described in Appendix A.5.3.
Layer controls:
These determine the actual data that will be plotted and what graphical form it takes. Layer controls can be added (using the Layers menu or corresponding toolbar buttons), removed (using the Remove Current Layer () toolbar button), and moved up and down (by dragging with the grab handle (). Each one contributes a layer or layers to the plot. Layers lower down the list are plotted later (perhaps obscuring earlier ones), so you can drag them up and down until you have the layers you want on top. The different layer controls are described in Appendix A.5.4.

The toolbar contains the following actions (repeated in the menus):

Float Controls
Display control panel in a floating window rather than at the bottom of the plot window, as described above.
Add Table Layer
Add a new table layer control to the control stack.
Add Function Layer (plane plot only)
Add a new function layer control to the control stack. Note this option is currently only available for the Plane Plot.
Remove Current Layer
Deletes the currently selected layer control from the control stack.
Draw Subset Region
Allows you to draw a region on the screen defining a new Row Subset. When you have finished drawing it, click this button again to indicate you're done. See Appendix A.5.2.1 for more details.
Subset From Visible
Defines a new Row Subset consisting of only the points which are currently visible on the plotting surface. See Appendix A.5.2.1 for more explanation.
Replot
Redraws the current plot. It is usually not necessary to use this button, since if you change any of the plot characteristics with the controls in this window the plot will be redrawn automatically. However if you have changed the data, e.g. by editing cells in the Data Window, or by redefining a subset, the plot is not automatically redrawn. Clicking this button redraws the plot taking account of any changes to the table data.
Rescale
Rescales the axes of the current plot so that it contains all the data points in the currently selected subsets. By default the plot will be scaled like this, but it it may have changed because of changes in the subset selection or from zooming in or out.
Zoom In
Zooms the plot in around its centre. In most cases using the mouse wheel if available is a better option, but this button is available as an alternative.
Zoom Out
Zooms the plot out around its centre. In most cases using the mouse wheel if available is a better option, but this button is available as an alternative.
Lock Axes
Usually, when the data plotted has changed significantly, the axes are automatically rescaled so that all the points are visible. The application makes a guess about when it's a good idea to do this automatic rescaling. If you don't want it to auto-rescale, set this toggle button, and it won't rescale unless it really has to. This is not available for the Sky Plot.
Export Plot
Allows you to save the plot in a variety of graphics formats using the Plot Export window.


Next Previous Up Contents
Next: Defining Subsets by Region
Up: Layer Plot Windows
Previous: Differences From Classic Plot Windows

TOPCAT - Tool for OPerations on Catalogues And Tables
Starlink User Note253
TOPCAT web page: http://www.starlink.ac.uk/topcat/
Author email: m.b.taylor@bristol.ac.uk
Mailing list: topcat-user@bristol.ac.uk