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A few useful commands

It will be useful to have a list of the images stored on the disk. The command:

CREATE/ICAT mycat *.bdf

creates a catalog stored on the disk as the file mycat.cat which contains the list of all images present on the disk. It is better to enable this catalog for automatic use by all other commands using:

SET/ICAT mycat

which allows in any command to refer to a catalog image by the simplified syntax #n where n is the entry number of the image in the catalog.

The following commands are also useful:

READ/ICAT mycat

lists the contents of an image catalog.

PRINT/ICAT mycat

prints the contents of an image catalog on the default printer. See command ASSIGN/PRINT to change the default.

COMPUTE/IMAGE out = expression

performs arithmetic on images, for example:

COMPUTE/IMAGE out = img1 - img2

computes the difference of images img1.bdf and img2.bdf and stores the result in out.bdf.

STATIST/IMA frame

performs statistic on an image. It is possible to select a sub-window in interactive mode or direct mode.

STATIST/IMA frame CURSOR
STATIST/IMA frame area_spec

The following commands are related to graphic facilities:

PLOT/IMAGE, OVERPLOT/IMAGE
PLOT/TABLE, OVERPLOT/TABLE
GET/GCURSOR
SEND/PLOT, ASSIGN/PLOT

It is also useful to handle tables, using commands:

READ/TABLE table [column]
SELECT/TABLE table conditional_expression
STATIST/TABLE table column
COMPUTE/TABLE table out_column = expression


next up previous contents
Next: Preprocessing Up: Echelle Reduction Previous: On-line help
Petra Nass
1999-06-15