User manual

Note: Some UCD should not appear more than one time in a table (“meta_main”).
Hence, if the correspondence is displayed on a red background, it means that there is a
conflict between UCDs. To avoid this, you need to click on the dominating column name
by holding the Ctrl key. Without further indications, the first column from the first
catalogue will be dominating.
5.7 Column computer
Menu: catalogue => Add a new column …
catalogues give some measures that can be seen in the “measures panel” by selecting the
sources (see 5.1.6 measures). These measures are displayed as different columns with
values. Aladin gives you the opportunity to add columns, obtained by computing on the
other columns values. For example, it is
possible to create a “J-K” column giving the
difference between two magnitude
columns “J” and “K”.
Access to the window
The window to control the computing of a
new column can be accessed either by the
contextual menu in the “measures panel “
(right click or CTRL click), or with the
main menu “catalogue => add a new
column…”. In this last case, you need to
specify beforehand the concerned
catalogue by selecting it in the stack.
General information on the new
column
To create a new column, you need to
specify a name. You can also add a unit for
the new column, as well as the UCD that
should be associated (see 5.5 using filters).
You can also specify the number of
decimals for displaying values.
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