AIPS HELP file for CSPEC in 31DEC26
As of Sun Sep 13 2:53:11 2026
CSPEC: Task to compare spectra from 2 image cubes
INPUTS
INNAME Image name (name)
INCLASS Image name (class)
INSEQ 0.0 9999.0 Image name (seq. #)
INDISK 0.0 9.0 Disk drive #
BLC 0.0 4096.0 Bottom left corner 0->use all
TRC 0.0 4096.0 Top right corner 0 -> use all
IN2NAME Image 2 name (name)
IN2CLASS Image 2 name (class)
IN2SEQ 0.0 9999.0 Image 2 name (seq. #)
IN2DISK 0.0 9.0 Image 2 disk drive #
TBLC 0.0 4096.0 Bottom left corner image 2
TTRC 0.0 4096.0 Top right corner image 2
NBOXES 0.0 50.0 Number of boxes in CLBOX
CLBOX Windows to use
DOINVERS -1.0 1.0 > 0 compute outside windows
OPTYPE 'RMS ' straight rms
'ROBU' robust rms
'RMAD' median absolute
deviation -> rms
'FLUX' intensity sum in Jy
'AVER' intensity average
OPCODE 'PLOT' => plot 2 on top
'SEPA' => plot 2 separated
'SUM ' => plot img 1 + img 2
'DIFF' => plot img 1 - img 2
'MULT' => plot img 1 * img 2
'DIVI' => plot img 1 / img 2
PIXRANGE Range of intensities to plot
FUNCTYPE 'SR, 'CR' else linear
ZINC -8192.0 8192.0 Increment on freq axis.
< 0 => invert Z axis in plot
SMOOTH Frequency smoothing function
LTYPE -410.0 410.0 Type of labeling: 1 border,
2 no ticks, 3 standard, 4 rel
to center, 5 rel to subim cen
6 pixels, 7-10 as 3-6 with
only tick labels
<0 -> no date/timeN
DOCENTER -1.0 2.0 0 => plot line to points
1 => plot as step function
2 => plot with full boxes
DOTV -1.0 2.0 > 0 Do plot on the TV, else
make a plot file
= 2 Init full TV
GRCHAN 0.0 88.0 Main graphics channel
+ 10 * label graphics chan
DOPRINT -1.0 6.0 > 0 => write text file
1 => PLOTR format
2 => TV2IM format INNAME
3 => TV2IM format IN2NAME
4 => TV2IM format result
5 => Weights for INNAME
6 => Weights for IN2NAME
OUTFILE
Text file output:
' ' => 'HOME:CSPEC.print
XYRATIO 0.0 Stretch the X axis wrt Y axis
0 -> 1.33
HELP SECTION
CSPEC
Type: Task
Use : Task to plot and print the the brightness or rms of an area in the
first two axes of one or two images as a function of location on
the third axis of those images. It is probably best to set the
area to the full image. The images are read into memory one plane
at a time and the flux or rms are found by appropriate means. The
spectrum or spectra will be placed in a plot file and can be
displayed with the display task of the user's choice. Note that
the third axis does not have to be a spectral-line axis - all
standard axis types are allowed. However, when using two image
cubes, the third axis of the two must be the same.
If the third axis is FQID, the plots made will be adjusted to a
frequency axis with points placed appropriately. Slices made
will be interpolated onto a regular frequency grid.
Adverbs:
INNAME......Image 1 name(name). blank => any
INCLASS.....Image 1 name(class). blank => any
INSEQ.......Image 1 name(seq. #). 0 => any
INDISK......Image 1 disk drive # of image. 0 => any
BLC.........The Bottom Left-hand pixel of the subarray of image 1 to
be plotted. The value (0,0,...) means (1,1,1,1,1,1,1).
Axes 3-7 are used normally - e.g. BLC(3) to TRC(3)
defines the channels to be plotted.
TRC.........The Top Right-hand pixel of the subarray of image 1 to
be plotted. The value (0,0,...) means the top right hand
corner of the entire image.
IN2NAME.....Image 2 name(name). blank => no second image
IN2CLASS....Image 2 name(class). blank => no second image
IN2SEQ......Image 2 name(seq. #). 0 => any
IN2DISK.....Image 2 disk drive # of image. 0 => any
TBLC........The Bottom Left-hand pixel of the subarray of image 2 to
be plotted. The value (0,0,...) means (1,1,1,1,1,1,1).
Axis 3-7 use BLC and TRC
TTRC........The Top Right-hand pixel of the subarray of image 2 to
be plotted. The value (0,0,...) means the top right hand
corner of the entire image.
NBOXES......<= 0 compute over BLC to TRC
> 0 use the windows in CLBOX for the first 2 axes
This option requires the 2 images to have identical
first and second axes.
CLBOX.......Areas in the first two axes over which to compute the
spectrum. Up to 50 may be specified. An area is either
rectangular from CLBOX(1,i) to CLBOX(3.i} in X and
CLBOX(2,i) to CLBOX(4,i) in Y or it is circular indicated
by CLBOX(1,i) < 0 with CLBOX(2,i) the radius and
CLBOX(3,i) the center in X and CLBOX(4,i) the center in Y.
Boxes may overlap, a pixel will be counted only once.
DOINVERS....> 0 => do the operation outside the BLC/TRC or NBOXES
CLBOX region(s).
<= 0 => do inside those region(s).
OPTYPE......= 'RMS ' => the rms is computed using all included image
values
= 'ROBU' => the rms is computed using robust means that
exclude the most positive and negative values
= 'RMAD' => the rms is computed with median absolute
deviation and then scaled to the usual rms
= 'FLUX' => the image is summed and then converted from
Jy/beam to Jy if the first 2 axes are
celestial coordinates and have a Clean beam.
= 'AVER' => the average brightnes is used
= other => 'FLUX'
OPCODE..... = 'PLOT' => plot both spectra on top of each other
= 'SEPA' => add a constant to the 2nd spectrum so thw
they do not overlap in the plot
= 'SUM ' => plot image 1 + image 2
= 'DIFF' => plot image 1 - image 2
= 'MULT' => plot image 1 * image 2
= 'DIVI' => plot image 1 / image 2
= ' ' => 'PLOT' and IN2NAME = ' ' => 'PLOT'
PIXRANGE....Range of pixel values to plot; values below PIXR(1) are
set to PIXR(1), values above PIXR(2) are set to PIXR(2).
PIXR(1) >= PIXR(2) implies use the full range of pixel
values in the image. In 'SEPA', PIXR is applied to each
spectrum before they are separated.
ZINC........Increment between plotted pixels on 3rd axis.
If < 0, abs(ZINC) is used and the Z axis is inverted
when listing and plotting.
SMOOTH.....Specifies the type of spectral smoothing to be applied to
a uv database . The default is not to apply any smoothing.
The elements of SMOOTH are as follows:
SMOOTH(1) = type of smoothing to apply: 0 => no smoothing
To smooth:
1 => Hanning, 2 => Gaussian, 3 => Boxcar, 4 => Sinc
5 => Hanning, 6 => Gaussian, 7 => Boxcar, 8 => Sinc
SMOOTH(2) = the "diameter" of the function, i.e. width
between first nulls of Hanning triangle and sinc
function, FWHM of Gaussian, width of Boxcar. Defaults
(if < 0.1) are 4, 2, 2 and 3 channels for SMOOTH(1) =
1 - 4 and 5 - 8, resp.
SMOOTH(3) = the diameter over which the convolving
function has value - in channels. Defaults: 1,3,1,4
times SMOOTH(2) used when input SMOOTH(3) < net
SMOOTH(2).
Hanning, Gaussian, and Sinc functions are always
symmetric. Boxcar allows only integer widths and has value
1.0 in all included channels. If the integer is odd, the
function is symmetric. If it is even, the function is
asymmetric having one more channel included to the
"right". Thus width 2 averages channels 1 and 2 in output
channel 1. Width 4 averages channels 1 through 4 in
output channel 2. The frequency reference pixel is
suitably adjusted in such cases. This is a change from
symmetric boxcars made in March 2021.
NOTE: smoothing is not recommended in Frequency ID axes.
LTYPE.......Labelling type, see HELP LTYPE for details:
1 = border, 2 = no ticks, 3 or 7 = standard, 4 or 8 =
relative to ref. pixel, 5 or 9 = relative to subimage
(BLC, TRC) center, 6 or 10 = pixels. 7-10 all labels
other than tick numbers and axis type are omitted.
Less than 0 is the same except that the plot file
version number and create time are omitted.
Add n * 100 to alter the metric scaling.
DOCENTER....False (<= 0) means to draw plot lines between the data
points of the "spectrum" producing a jagged looking plot.
=1 means to plot 1-channel horizontal lines centered on
each data point and connected to adjacent points by
vertical lines producing a step function like plot.
=2 means to plot 1-channel horizontal lines centered on
each data point and connected to adjacent points by
vertical lines with those lines extended to the bottom
of the plot producing a histogram-like plot.
DOTV........> 0 => plot directly on the TV device, otherwise make a
plot file for later display on one or more devices
(including the TV if desired).
>= 1.5 => initialize all of the TV, not just the
grey-scale and graphics planes used
GRCHAN......Graphics channel (1 - 7) to use for line drawing.
A value of 0 causes more than one graphics channel to be
used. To specify a channel to be used for plot labels
add 10 * that graphics channel number. If the label
channel is zero, it is set to GRCHAN. Use this to make
labels 1 color and plot multiple plots on top of each
other using different GRCHANs. Note if one of the
GRCHAN (lower digits) is to equal the label channel,
then that must be the last of the overplots since the
graphics channel is cleared before making the labels.
Do not use the label channel if you plan to use TVCPS
and specify the label channel there as well. Note
that channels 5, 6, and 7 are usable for labels and
are not useful for overplotting.
DOPRINT.....1 => write a text file in a format suitable as input
to PLOTR (includes all 3 types if present)
2 => write a text file suitable as input to TX2IM from
INNAME spectrum
3 => write a text file suitable as input to TX2IM from
IN2NAME spectrum if present
4 => write a text file suitable as input to TX2IM from
INNAME combined with IN2NAME spectrum if presenyt
5 => write a weights file from INNAME (OPCODE rms)
6 => write a weights file from IN2NAME (OPCODE rms)
The weights are scaled so that the maximum is 100.
They are 1/rms^2 and may be used as INFILE in FARS,
RMFIT, and STACK and as INTEXT in IMLIN, REWGT, SQASH,
and UVLIN. Other uses may also exist.
OUTFILE.....Disk file name in which to save the DOPRINT > 0 output.
If OUTFILE pre-exists, the new output will be appended.
XYRATIO.....The ratio of the axes X to Y in the plot. 1.0 makes a
square plot. 0 -> 1.3 (about the usual ratio of X to Y
on the TV screen or A format paper).
EXPLAIN SECTION