Activation Window
The Activation Window allows you to configure an action to perform
when a table row is activated
by clicking on a row in the Data Window or a point in the Plot Window.
It can be obtained by clicking the Activation Action
selector at the bottom of the properties panel in the Control Window.
You have various options for how to define the action.
On the left of the window is a list of options; you have to choose
one of these to determine what kind of action will take place.
When you click on one of these options the corresponding
controls on the right hand side will become enabled:
use these to select the details of the action and then
click the OK button so that subsequent
activation events will cause the action you have defined
(or Cancel so that they won't).
When you click OK the Activation Action
in the control window will indicate the action you have configured.
The available options are as follows:
-
No Action
- If this is selected, no special action will take place when a
row is activated. This is the default.
-
Display Cutout Image
- This option presents an easy-to-use way of popping up a
cutout image from an image server displaying a region of sky
around an activated row.
You need to select the columns in your table which
represent Right Ascension and Declination, including the units
in which they are entered in the table (TOPCAT may be able to
guess some or all of this information based on column names, UCDs
and unit values, in which case it will enter its guesses in the
selectors for you to accept or change).
You also need to select the size in pixels of the image you want
to see and the name of the survey which will supply the image
from one of the listed ones:
- SuperCOSMOS All-Sky Blue
- SuperCOSMOS All-Sky Red
- SDSS Colour Images (note does not provide all-sky coverage)
When you activate the row, the program will attempt to contact the
web server which provides these images, retrieve the image, and
display it in an image viewer window.
-
Display Named Image
- This option is suitable if one of the columns in your table
gives the location (filename or URL) of an image file.
The image may be in FITS, GIF, JPEG or PNG format, optionally
compressed using gzip, Unix compress, or bzip2 format.
Select the column which contains the location, and activating a
row will pop up an image viewer to display it.
-
Display Named Spectrum
- This option is suitable if one of the columns in your table
gives the location (filename or URL) of a spectrum file.
The spectrum may be in FITS or text format, optionally compressed.
Select the column which contains the location, an activating a
row will try to pop up a spectrum viewer to display it.
Note this may not be possible if some components are not installed
(see Appendix A.9.1).
-
Execute Custom Code
- This option must be used if none of the others
(which are fairly restrictive) do what you want.
It is highly flexible, but not so easy to use.
What you have to do is to write an expression following the rules
in Section 6 involving some
of the column names which will be invoked when a row is activated.
This expression will typically have the effect of popping up
an image or a spectrum in a viewer,
but, especially if you link in your own functions
(see Section 6.8) it can do pretty much anything.
Functions which are expected to be useful for activation actions
are described in Section 6.5.2 and include some
general-purpose ones
(displayImage and displaySpectrum to display
an image or spectrum in an external viewer) as well as a few
which are relevant to particular survey data, for instance the
spectra2QZ() function, which will pop up a spectrum
viewer displaying all the spectra related to a given row of 2QZ
survey data based on the contents of its NAME column.