Once the SXT data are read into index and data using YODAT or RD_SDA, it is very simple to display images. A general purpose routine called STEPPER is the most common method used.
STEPPER takes a data cube (data) and allows a user to step
through the images and to display them as a movie. If the index
is passed into STEPPER (as shown in 2 of the examples below) it is
possible to chose an option to display light curves.
Some sample calls are:
IDL> stepper, data
IDL> stepper, data, info_array
IDL> stepper, index, data, xsiz=512
IDL> stepper, index, data, info_array
where info_array and xsiz are optional parameters. xsiz indicates
the size of the displayed image you want (must be an
integer multiple of the original array). It is a
window driven program.
Some other keyword options are start=start to specify the starting image to display; /noscale to not perform automatic scaling on each individual image (uses TV instead of TVSCL); subscript=ss to specify the image numbers to display (default is to display all images in the data cube); /filter_panels to display each unique filter in a different location on the window; /sequence_panels to display each unique image sequence in a different location on the window.
When STEPPER begins, the following menu is displayed.
-------- STEPPER Options --------
There are 259 images in the array
There are 259 images selected
Enter "b" to step backwards "h" to call HARDCOPY
"s" to select new start index "z" for ZOOM
"c" to call LOADCT "x" for XLOADCT
"p" to call the IDL PROFILES routine "l" to call light curve routine
"g" to overlay SXT solar grid "o" for observing region location
"q" to quit "m" for movie mode
"?" to display this help menu "anything else" to step forward
The user only needs to press the key to select the option (no <CR> required). It is possible to overlay a grid showing the solar limb and latitude/longitude lines for either full frame or partial frame images. The ``l'' option calls LCUR_IMAGE and the user should read section 4.3 for more details.
The routine XSTEPPER is a widget driven routine which operates in a manner
similar to STEPPER, but has some other capabilities. A sample call is:
IDL> xstepper, data, info_array
It is possible to load a data cube into a widget to be ``animated'' using
the routine XMOVIE (which is simply an interface for IDL's XINTERANIMATE).
The speed which the frames can be displayed is quite fast.
There are some memory restrictions which do not allow large data cubes.
Some sample calls are:
IDL> xmovie, data
IDL> xmovie, data, ss=ss ; only displaying images listed in ss
A final popular routine for displaying images is the routine XY_RASTER.
This routine will make a raster pattern of a time series of images
to display time evolution.
The images start at upper left and go to lower right,
and the time is optionally written at the bottom of each
image. Some sample calls are:
IDL> xy_raster, index, data
IDL> xy_raster, index, data, 3, ss=ss
The second example blows the image up to three times its input size and
only displays the images listed in the array ss.