ARDOUT = FILENAME (Write)
Name of the text file in which to store the
description of the selected regions.
DEVICE = DEVICE (Read)
The graphics device on which the
regions are to be selected.
[Current graphics device
OPERANDS() = _INTEGER (Read)
A pair of
indices for the regions which are to be combined together using the operator specified by Parameter
OPERATOR. If the operator is
"NOT", then only one region index need be supplied. Region
indices are displayed by the
"List" option (see Parameter OPTION).
The operator to use when combining two regions into a single region.
The pixels included in the resulting region depend on which of the following operators is
"AND" — Pixels are included if they are in both of the regions specified by Parameter OPERANDS.
"EQV" — Pixels are included if they are in both or neither of the regions specified by Parameter
"NOT" — Pixels are included if they are not inside the region specified by Parameter OPERANDS.
"OR" — Pixels are included if they are in either of the regions specified by Parameter OPERANDS.
Note, an OR operator is implicitly assumed to exist between each pair of adjacent regions unless some
other operator is specified.
"XOR" — Pixels are included if they are in one, but not both, of the regions specified by
OPTION= LITERAL (Read)
A value for this parameter is
obtained when you choose to end cursor input (by pressing the relevant button as described
when the application starts up). It determines what to do next. The following options are
"Combine" — Combine two previously defined regions into a single region using a Boolean operator,
or invert a previously defined region using a Boolean .NOT. operator. See parameters OPERANDS
and OPERATOR. The original regions are deleted and the new combined (or inverted) region is added
to the end of the list of defined regions.
"Delete" — Delete previously defined regions, see parameter REGIONS.
"Draw" — Draw the outline of the union of one or more previously defined regions, see Parameter
"Exit" — Write out the currently defined regions to a text file and exit the application.
"List" — List the textual descriptions of the currently defined regions on the screen. Each region is
described by an index value, a keyword corresponding to the shape, and various arguments describing
the extent and position of the shape. These arguments are described in the “Notes” section
"Multi" — The cursor is displayed and you can then identify multiple regions of the current shape,
without being re-prompted for OPTION after each one. These regions are added to the end of the list
of currently defined regions. If the current shape is
"Whole" (see Parameter
SHAPE) then multiple regions cannot be defined and the selected option automatically reverts to
"Single" — The cursor is displayed and you can then identify a single region of the current shape.
You are re-prompted for Parameter OPTION once you have defined the region. The identified region
is added to the end of the list of currently defined regions.
"Shape" — Change the shape of the regions created by the
"Multi" options. This causes
a new value for Parameter SHAPE to be obtained.
"Style" — Change the drawing style by providing a new value for Parameter STYLE.
"Quit" — Quit the application without saving the currently defined regions.
"Undo" — Undo the changes made to the list of ARD regions by the previous option. Note, the undo
list can contain upto 30 entries. Entries are only stored for options which actually produce a change in
the list of regions.
REGIONS() = LITERAL (Read)
The list of regions to be deleted or drawn.
Regions are numbered consecutively from 1 and can be listed using the
(see Parameter OPTION). Single regions or a set of adjacent regions may be specified, e.g.
will delete regions 4,6,7,8,9,12,14,15,16. (Note that the brackets are
required to distinguish this array of characters from a single string including commas. The
brackets are unnecessary when there is only one item.) The numbers need not be in ascending
If you wish to delete or draw all the regions enter the wildcard
will delete or draw from 5 to the last region.
SHAPE = LITERAL (Read)
The shape of the regions to
be defined using the cursor. After selecting a new shape, you are immediately requested to identify
multiple regions as if
had been specified for Parameter OPTION. The currently available
shapes are listed below.
"Box" — A rectangular box with sides parallel to the co-ordinate axes, defined by its centre and one of
"Circle" — A circle, defined by its centre and radius.
"Column" — A single value on Axis 1, spanning all values on Axis 2.
"Ellipse" — An ellipse, defined by its centre, one end of the major axis, and one other point which
can be anywhere on the ellipse.
"Frame" — The whole image excluding a border of constant width, defined by a single point on the
"Point" — A single pixel.
"Polygon" — Any general polygonal region, defined by up to 200 vertices.
"Rectangle" — A rectangular box with sides parallel to the co-ordinate axes, defined by a pair of
diagonally opposite corners.
"Rotbox" — A rotated box, defined by both ends of an edge, and one point on the opposite
"Row" — A single value on Axis 2, spanning all values on Axis 1.
"Whole" — The whole of the displayed image.
STARTUP = LITERAL (Read)
Determines if the
application starts up in
"Single" mode (see Parameter OPTION).
Used to confirm that it is OK to proceed with an
"Undo" option. The
consequences of proceeding are described before the parameter is obtained.
ardgen extract.txt circle exit startup=single This example allows you to create a text file
extract.txt) describing a single circular region of the image displayed on the current graphics
device. The application immediately exits after the region has been identified. This example
may be useful in scripts or command procedures since there is no prompting.
An image must previously have been displayed on the graphics device.
The arguments for the textual description of each shape are as follows :
"Box" — The co-ordinates of the centre, followed by the lengths of the two sides.
"Circle" — The co-ordinates of the centre, followed by the radius.
"Column" — The Axis 1 co-ordinate of the column.
"Ellipse" — The co-ordinates of the centre, followed by the lengths of the semi-major
and semi-minor axes, followed by the angle between Axis 1 and the semi-major axis (in
"Frame" — The width of the border.
"Point" — The co-ordinates of the pixel.
"Polygon" — The co-ordinates of each vertex in the order given.
"Rectangle" — The co-ordinates of two diagonally opposite corners.
"Rotbox" — The co-ordinates of the box centre, followed by the lengths of the two sides, followed by
the angle between the first side and Axis 1 (in radians).
"Row" — The Axis 2 co-ordinate of the row.
"Whole" — No arguments.
The shapes are defined within the current co-ordinate Frame of the displayed NDF. For instance, if the
current co-ordinate Frame of the displayed NDF is RA/DEC, then
"COLUMN" regions will be curves of
"ROW" regions will be curves of constant RA (assuming Axis 1 is RA and Axis 2 is DEC),
straight lines will correspond to geodesics, etc. Numerical values will be stored in the output text file
in the current co-ordinate Frame of the NDF. WCS information will also be stored in the output text
file allowing the stored positions to be converted to other systems (pixel co-ordinates, for instance).