AIPS HELP file for HLPRMFIT in 31DEC24
As of Mon May 6 13:22:50 2024
HLPRMFIT Run-time help for task RMFIT
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EXIT
This option causes the interactive portion of RMFIT to finish. The
task then resumes, AIPS, releases the TV device, and, if DOOUTPUT is
greater than zero, writes the output cataloged images. The residual is
written if DOOUTPUT = 1 or 3 and the parameter images are written if
DOOUTPUT = 2 or 3.
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SET MIN S/N
This option allows you to specify the minimum signal to noise ratio in
total polarization for acceptable solutions. One ratio for each of the
NGAUSS components will be used. The REDO ALL and FLAG ALL operations
use this value to test whether a solution should be redone or flagged,
resp. A value of 0 or less will cause the test for the specific
polarization component to be ignored. The current values of these
parameters are displayed above the menu. If you enter fewer than NGAUS
values, the first value you entered will be used for all omitted values.
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SET MIN P
This option allows you to specify the total polarization (at 1 GHz) for
acceptable solutions. One minium for each of the NGAUSS components will
be used. The REDO ALL and FLAG ALL operations use this value to test
whether a solution should be redone or flagged, resp. A value of 0 or
less will cause the test for the specific polarization component to be
ignored. The current values of these parameters are displayed above the
menu. If you enter fewer than NGAUS values, the first value you entered
will be used for all omitted values.
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SET MAX RESID
This option allows you to specify the maximum residual for acceptable
solutions. You will be prompted in the terminal window to enter one
value in the units of the input image. The REDO ALL and FLAG ALL
operations use this value to test whether a solution should be redone
or flagged, resp. A value of 0 or less will cause the test for peak
residual to be ignored. The current value of this parameter is
displayed above the menu.
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SET RM RANGE
This option allows you to specify the minimum and maximum rotation
measure in acceptable solutions. One range for each of the NGAUSS
components will be used. Units are radians per meter squared. The
REDO ALL and FLAG ALL operations use these values to test whether a
solution should be redone or flagged, resp. When the maximum is less
than or equal the minimum the test on rotation measure for the specific
polarization component is ignored. The current values of these
parameters are displayed above the menu. You may enter fewer than
2 * NGAUSS values. The values for the first Gaussian are used for the
values you did not enter. This is probably a poor idea.
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SET MAX THETA ER
This option allows you to specify the maximum uncertainty in component
POLARIZATION ANGLE for acceptable solutions. One maximum for each of
the NGAUSS components will be used. The REDO ALL and FLAG ALL
operations use this value to test whether a solution should be redone
or flagged, resp. A value of 0 or less will cause the test for the
specific polarization component to be ignored. The current values of
these parameters are displayed above the menu. If you enter fewer than
NGAUS values, the first value you entered will be used for all omitted
values.
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SET SPIX RANGE
This option allows you to specify the minimum and maximum spectral index
in acceptable solutions. One range for each of the NGAUSS components
will be used. Spectral index is unitless. The REDO ALL and FLAG ALL
operations use these values to test whether a solution should be redone
or flagged, resp. When the maximum is less than or equal the minimum
the test on spectral index for the specific polarization component is
ignored. The current values of these parameters are displayed above
the menu. You may enter fewer than 2 * NGAUSS values. The values for
the first Gaussian are used for the values you did not enter. This may
be a poor idea.
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SET THICKNESS MAX
This option allows you to specify the maximum thickness parameter in
acceptable solutions. One value for each of the NGAUSS components will
be used. The units are radians per meter squared. The REDO ALL and
FLAG ALL operations use these values to test whether a solution should
be redone or flagged, resp. When the maximum is less than or equal 0
the test on thickness parameter for the specific polarization component
is ignored. The current values of these parameters are displayed above
the menu. You may enter fewer than NGAUSS values. The value for the
first Gaussian is used for the values you did not enter. This may be
okay.
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REDO ALL
This option allows you to try to improve selected solutions. The
operation examines all pixels for which there is a solution. If (1)
the signal-to-noise ratio in total polarization in any component is
below the minimum for that component, (2) the rotation measure in any
component is outside the range of rotation measures for that
component, (3) the uncertainty in the polarization angle of any
component is greater than the maximum for that component, (4) the
spectral index or thickness is out of range, or (5) the peak residual
after the fit components are subtracted is greater than the maximum
residual, the solution for that row of the input image is done over.
TV control of the initial guess is allowed even for single polarization
fits in the hope of forcing a better solution.
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FLAG ALL
This option allows you to flag selected solutions. The operation
examines all pixels for which there is a solution. If (1) the
signal-to-noise ratio in total polarization in any component is below
the minimum for that component, (2) the rotation measure in any
component is outside the range of rotation measures for that
component, (3) the uncertainty in the polarization angle of any
component is greater than the maximum for that component, (4) the
spectral index or thickness is out of range, or (5) the peak residual
after the fit components are subtracted is greater than the maximum
residual, the solution for that row of the input image is marked as
failed.
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OFF ZOOM
This option in the main menu allows you to turn off the zoom function
selected with TVZOOM in the image display menu.
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OFF TRANSFER
This option in the main menu turns of any black-and-white enhancements
done by TVTRANSF and any coloring done by TVPSEUDO or TVPHLAME in the
image display menu.
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SET DOOUTPUT
The option cycles the value of the DOOUTPUT adverb from 0 through 3
and back to 0. The value of DOOUTPUT, displayed at the top of the TV
screen, when the EXIT option is selected determines whether the residual
image is written to disk (DOOUTPUT = 1 or 3) and whether the parameter
images are written to disk (DOOUTPUT = 2 or 3).
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ADD TO LIST
This option prompts you in the terminal window to enter 2 integers which
specify the X, Y pixel coordinates in the output image of a pixel for
which you would like to revisit the fit. You can prepare a list of
pixels for revisiting using this option or CURVALUE in the image display
menu. You can list these pixels (SHOW LIST) and you can the repeat the
fitting of them with REDO LIST or simply flag them out with FLAG LIST.
If you want to remove a pixel from the list, enter its pixel coordinates
with negative signs. Note that the list may include pixels for which
there is not currently a solution.
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SHOW LIST
This option displays in the message window the current list of output
image pixels which will be revisited with the REDO LIST and FLAG LIST
options. ADD TO LIST may be used to add a pixel to or remove a pixel
from this list.
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REDO LIST
The output image pixels in the current list are revisited to see if it
is possible to improve upon the current solutions (if any). The usual
options to mark BAD, to REDO, to QUIT, and to turn off the TV
interaction are all offered. The list is processed in inverse order
and its length reduced as one goes. Thus a QUIT in the middle will
leave the first part of the list untouched. Note that turning off the
TV will eliminate any chance to enter better guesses to force a better
fit.
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FLAG LIST
The output pixels in the current list are revisited in the solutions
table and those solutions are marked as failed. The list is reset
after this operation.
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SWAP LIST 1-2
This option allows you to swap the solutions for polarization component
1 with those of polarization component 2 at all of the pixels in the
list. The list is reset after this operation.
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SWAP LIST 1-3
This option allows you to swap the solutions for polarization component
1 with those of polarization component 3 at all of the pixels in the
list. The list is reset after this operation.
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SWAP LIST 2-3
This option allows you to swap the solutions for polarization component
2 with those of polarization component 3 at all of the pixels in the
list. The list is reset after this operation.
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SWAP LIST 1-4
This option allows you to swap the solutions for polarization component
1 with those of polarization component 4 at all of the pixels in the
list. The list is reset after this operation.
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SWAP LIST 2-4
This option allows you to swap the solutions for polarization component
2 with those of polarization component 4 at all of the pixels in the
list. The list is reset after this operation.
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SWAP LIST 3-4
This option allows you to swap the solutions for polarization component
3 with those of polarization component 4 at all of the pixels in the
list. The list is reset after this operation.
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SHOW IMAGE P0_
These options allow you to enter an image display mode while displaying
an image of the total polarization of the selected component. The
value range in the image is displayed on the message terminal and at
the top of the TV screen in input image units. The image display mode
offers a menu including OFF TRANSF, OFF COLOR, TVTRANSF, TVPSEUDO,
TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are the familiar
operations except that CURVALUE allows you to add to a pixel list for
later re-examination of the solutions. You can also choose to re-load
the image to the TV with a selection of transfer functions.
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SHOW IMAGE EP0_
These options allow you to enter an image display mode while displaying
an image of the uncertainty in the total polarization of the selected
component. The value range in the image is displayed on the message
terminal and at the top of the TV screen in input image units. The
image display mode offers a menu including OFF TRANSF, OFF COLOR,
TVTRANSF, TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are
the familiar operations except that CURVALUE allows you to add to a
pixel list for later re-examination of the solutions. You can also
choose to re-load the image to the TV with a selection of transfer
functions.
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SHOW IMAGE TH_
These options allow you to enter an image display mode while displaying
an image of the polarization position angle at zero wavelength of the
selected component. The value range in the image is displayed on the
message terminal and at the top of the TV screen in degrees. The
image display mode offers a menu including OFF TRANSF, OFF COLOR,
TVTRANSF, TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are
the familiar operations except that CURVALUE allows you to add to a
pixel list for later re-examination of the solutions. You can also
choose to re-load the image to the TV with a selection of transfer
functions.
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SHOW IMAGE ETH_
These options allow you to enter an image display mode while displaying
an image of the uncertainty in the polarizatopn position angle at zero
wavelength of the selected component. The value range in the image is
displayed on the message terminal and at the top of the TV screen in
degrees. The image display mode offers a menu including OFF TRANSF,
OFF COLOR, TVTRANSF, TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN.
All are the familiar operations except that CURVALUE allows you to add
to a pixel list for later re-examination of the solutions. You can
also choose to re-load the image to the TV with a selection of
transfer functions.
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SHOW IMAGE RM_
These options allow you to enter an image display mode while displaying
an image of the rotation of the selected component. The value range
in the image is displayed on the message terminal and at the top of
the TV screen in radians/m/m. The image display mode offers a menu
including OFF TRANSF, OFF COLOR, TVTRANSF, TVPSEUDO, TVPHLAME, TVZOOM,
CURVALUE, and RETURN. All are the familiar operations except that
CURVALUE allows you to add to a pixel list for later re-examination of
the solutions. You can also choose to re-load the image to the TV
with a selection of transfer functions.
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SHOW IMAGE ERM_
These options allow you to enter an image display mode while displaying
an image of the uncertainty in the rotation measure of the selected
component. The value range in the image is displayed on the message
terminal and at the top of the TV screen in radians/m/m. The image
display mode offers a menu including OFF TRANSF, OFF COLOR, TVTRANSF,
TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are the familiar
operations except that CURVALUE allows you to add to a pixel list for
later re-examination of the solutions. You can also choose to re-load
the image to the TV with a selection of transfer functions.
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SHOW IMAGE Q0_
These options allow you to enter an image display mode while displaying
an image of the Q polarization at zero wavelength of the selected
component. The value range in the image is displayed on the message
terminal and at the top of the TV screen in image units. The image
display mode offers a menu including OFF TRANSF, OFF COLOR, TVTRANSF,
TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are the
familiar operations except that CURVALUE allows you to add to a pixel
list for later re-examination of the solutions. You can also choose
to re-load the image to the TV with a selection of transfer functions.
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SHOW IMAGE EQ0_
These options allow you to enter an image display mode while displaying
an image of the uncertainty in the Q polarization at zero wavelength of
the selected component. The value range in the image is displayed on
the message terminal and at the top of the TV screen in image units.
The image display mode offers a menu including OFF TRANSF, OFF COLOR,
TVTRANSF, TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are
the familiar operations except that CURVALUE allows you to add to a
pixel list for later re-examination of the solutions. You can also
choose to re-load the image to the TV with a selection of transfer
functions.
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SHOW IMAGE U0_
These options allow you to enter an image display mode while displaying
an image of the U polarization at zero wavelength of the selected
component. The value range in the image is displayed on the message
terminal and at the top of the TV screen in image units. The image
display mode offers a menu including OFF TRANSF, OFF COLOR, TVTRANSF,
TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are the
familiar operations except that CURVALUE allows you to add to a pixel
list for later re-examination of the solutions. You can also choose
to re-load the image to the TV with a selection of transfer functions.
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SHOW IMAGE EU0_
These options allow you to enter an image display mode while displaying
an image of the uncertainty in the U polarization at zero wavelength of
the selected component. The value range in the image is displayed on
the message terminal and at the top of the TV screen in image units.
The image display mode offers a menu including OFF TRANSF, OFF COLOR,
TVTRANSF, TVPSEUDO, TVPHLAME, TVZOOM, CURVALUE, and RETURN. All are
the familiar operations except that CURVALUE allows you to add to a
pixel list for later re-examination of the solutions. You can also
choose to re-load the image to the TV with a selection of transfer
functions.
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RETURN
This option returns from the image display menu to the primary menu to
select a different image to display, to set data selection values, and
to revisit selected solutions in order to modify or flag them.
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LOAD AS LN
This option re-loads the current image using a linear transfer function
from the image minimum to its maximum. The image you are now viewing
was loaded with the L2 (extreme log) transfer function.
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LOAD AS SQ
This option re-loads the current image using a square root transfer
function from the image minimum to its maximum. The image you are now
viewing was loaded with the LN (linear) transfer function.
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LOAD AS LG
This option re-loads the current image using a logarithmic transfer
function from the image minimum to its maximum. The image you are now
viewing was loaded with the SQ (square root) transfer function.
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LOAD AS L2
This option re-loads the current image using a more extreme logarithmic
transfer function from the image minimum to its maximum. The image you
are now viewing was loaded with the LG (logarithmic) transfer function.
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SET WINDOW
This option turns on a standard TVWINDOW operation to set the lower left
corner and upper right corner of a sub-image that you would like to view
in more detail. Buttons A and B switch between corners and buttons C
and D set the desired window which is immediately displayed.
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RESET WINDOW
This option returns the image display to the full image. This option is
available in the edit screen and the image display screen.
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LABEL WEDGE?
Turns on or off the labeling of the step wedge plotted at the bottom
of each image.
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OFF TRANSF
This option turns of any black-and-white enhancements done in TVTRANSF.
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OFF COLOR
This options turns of any color enhancements done in TVPSEUDO or
TVPHLAME. Has no effect if the image is in black and white.
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TVTRANSF
This option allows you to set the black-and-white transfer function
using the TV cursor to control intercept and slope. Buttons A and B
turn a plot of the LUT on and off, button C reverses the sign of the
slope, and button D ends the enhancement and returns to the menu.
Instructions appear on the message screen.
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TVPSEUDO
This option allows you to set the color transfer function using the TV
cursor. Button A loops through all possible RGB triangles, button B
selects a circle in hue (which is very useful for phase displays),
button C selects several color contours, and button D ends the
enhancement and returns to the menu. As in AIPS, the TV cursor is used
to adjust the colors within the selected function. Instructions appear
on the message screen.
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TVPHLAME
This option allows you to set the color transfer function using the TV
cursor and a flame-like color scheme. Buttons A and B cycle through the
sequence of all possible color combinations, while buttons C and D end
the enhancement and return to the menu. The TV cursor X position
adjusts the image intensity at which the color turns more white, while
the Y position adjusts the way colors add (the gamma). Instructions
appear on the message screen.
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TVZOOM
This option lets you set the TV zoom magnification factor and to set the
point about which the zoom takes place. The cursor points at the zoom
center which will be shifted to the center of the screen. A hit on
buttons A or B increments the magnification factor and on button C
decrements the magnification factor in a circular fashion. Hit button D
to exit. Instructions appear on the message screen.
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CURVALUE
To perform an interactive display of the pixel locations and values of
the image visible on the TV. The X and Y pixel coordinates, the pixel
value, and the units of the pixel value are displayed in TV graphics
channel 1 at the upper left of the display. The cursor position
determines which pixel is shown. Unlike other CURVALUEs in AIPS,
buttons A and B allow you to add the selected pixel to a list of pixels
to be flagged or re-fit at a later time. Buttons C and D end the
display and returns to the menu. Instructions appear on the message
screen. The pixel values are read from the image in memory and hence
preserve accuracy.
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SWAP 1-2
This option allows you to select polygonal regions for which you wish to
swap the solution for component 1 with that of component 2. The
interactive polygon setting operation starts in the "set polygon n" mode
where button A selects a vertex in the polygon, B sets the last vertex
in the polygon and gets ready to set polygon n+1, C sets the last
vertex and enters a vertex editing mode, and D sets the last vertex
and exits the polygon setting. In the vertex editing mode, move the
cursor to a vertex to be moved and press button A or B to reset its
position. After moving it to the desired point, press button A or B
to fix that point and restart the vertex editing mode. Press button C
to fix that point and then start creating polygon n+1. Press button D
to fix that point and exit the polygon setting. Once button D has
been set, the selected areas of pixels have their solutions swapped.
The images are updated and reloaded automatically.
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SWAP 1-3
This option allows you to select polygonal regions for which you wish to
swap the solution for component 1 with that of component 3. The
interactive polygon setting operation starts in the "set polygon n" mode
where button A selects a vertex in the polygon, B sets the last vertex
in the polygon and gets ready to set polygon n+1, C sets the last
vertex and enters a vertex editing mode, and D sets the last vertex
and exits the polygon setting. In the vertex editing mode, move the
cursor to a vertex to be moved and press button A or B to reset its
position. After moving it to the desired point, press button A or B
to fix that point and restart the vertex editing mode. Press button C
to fix that point and then start creating polygon n+1. Press button D
to fix that point and exit the polygon setting. Once button D has
been set, the selected areas of pixels have their solutions swapped.
The images are updated and reloaded automatically.
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SWAP 2-3
This option allows you to select polygonal regions for which you wish to
swap the solution for component 2 with that of component 3. The
interactive polygon setting operation starts in the "set polygon n" mode
where button A selects a vertex in the polygon, B sets the last vertex
in the polygon and gets ready to set polygon n+1, C sets the last
vertex and enters a vertex editing mode, and D sets the last vertex
and exits the polygon setting. In the vertex editing mode, move the
cursor to a vertex to be moved and press button A or B to reset its
position. After moving it to the desired point, press button A or B
to fix that point and restart the vertex editing mode. Press button C
to fix that point and then start creating polygon n+1. Press button D
to fix that point and exit the polygon setting. Once button D has
been set, the selected areas of pixels have their solutions swapped.
The images are updated and reloaded automatically.
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SWAP 1-4
This option allows you to select polygonal regions for which you wish to
swap the solution for component 1 with that of component 4. The
interactive polygon setting operation starts in the "set polygon n" mode
where button A selects a vertex in the polygon, B sets the last vertex
in the polygon and gets ready to set polygon n+1, C sets the last
vertex and enters a vertex editing mode, and D sets the last vertex
and exits the polygon setting. In the vertex editing mode, move the
cursor to a vertex to be moved and press button A or B to reset its
position. After moving it to the desired point, press button A or B
to fix that point and restart the vertex editing mode. Press button C
to fix that point and then start creating polygon n+1. Press button D
to fix that point and exit the polygon setting. Once button D has
been set, the selected areas of pixels have their solutions swapped.
The images are updated and reloaded automatically.
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SWAP 2-4
This option allows you to select polygonal regions for which you wish to
swap the solution for component 2 with that of component 4. The
interactive polygon setting operation starts in the "set polygon n" mode
where button A selects a vertex in the polygon, B sets the last vertex
in the polygon and gets ready to set polygon n+1, C sets the last
vertex and enters a vertex editing mode, and D sets the last vertex
and exits the polygon setting. In the vertex editing mode, move the
cursor to a vertex to be moved and press button A or B to reset its
position. After moving it to the desired point, press button A or B
to fix that point and restart the vertex editing mode. Press button C
to fix that point and then start creating polygon n+1. Press button D
to fix that point and exit the polygon setting. Once button D has
been set, the selected areas of pixels have their solutions swapped.
The images are updated and reloaded automatically.
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SWAP 3-4
This option allows you to select polygonal regions for which you wish to
swap the solution for component 3 with that of component 4. The
interactive polygon setting operation starts in the "set polygon n" mode
where button A selects a vertex in the polygon, B sets the last vertex
in the polygon and gets ready to set polygon n+1, C sets the last
vertex and enters a vertex editing mode, and D sets the last vertex
and exits the polygon setting. In the vertex editing mode, move the
cursor to a vertex to be moved and press button A or B to reset its
position. After moving it to the desired point, press button A or B
to fix that point and restart the vertex editing mode. Press button C
to fix that point and then start creating polygon n+1. Press button D
to fix that point and exit the polygon setting. Once button D has
been set, the selected areas of pixels have their solutions swapped.
The images are updated and reloaded automatically.
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NEXT WINDOW
Very large images may not be able to fit on your TV. When the image
exceeds the size of the TV, the top line will show the component
number followed by a subimage number in parentheses and the NEXT
WINDOW option will appear. The first sub-images displayed is called
number 0 and shows the full image every n'th pixel in X and Y.
Sub-image 1 begins at the lower left, moves right, then back to the
left and up, and so forth until the top right is reached. Every pixel
is displayed in these sub-images. Use the NEXT WINDOW option to step
through the sub-images in a circular fashion.
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DO FIT
Selecting this option tells RMFIT to use the current initial guess to
try to fit the model parameters.
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RE-GUESS
Selecting this option tells RMFIT to request the input of a new initial
guess of the model parameters using the TV. You will be prompted, one
component at a time, to point at the position in RM of the component
(only the X position, the RM, matters).
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BAD
Selecting this option tells RMFIT to mark the current pixel as "bad"
in the model file and then go on to the next pixel.
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QUIT
Selecting this option causes RMFIT to exit cleanly. It may be
re-started later with the same model file to continue model fitting
and image editing.
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GOOD
Selecting this option tells RMFIT that the fit appears to be good.
The task stores the parameters in the model file and goes on to the
next pixel.
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TVOFF
Selecting this option turns off the TV interaction and tells RMFIT to
ncontinue fitting with its own self-generated initial guesses. The
interactive mode will be turned back on when the fit parameters are
outside a reasonable range of values, the RMS exceeds RMSLIMIT, or when
RMFIT reaches the image editing stage.
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HAND
Selecting this options tells the task that you wish to enter an initial
guess by typing in values in the AIPS terminal window (after prompting).
In RMFIT, the parameters are the polarization (Jy/beam), intrinsic angle
(degrees), rotation measure (radians/m/m), and possibly the spectral
index (unitless) or thickness (radians/m/m).
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Selecting this option tells RMFIT to try the fitting again using only
the specified number of Components.
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PIXRANGE
Selecting this option tells RMFIT to re-plot the Q and U spectra or P
and angle spectra using the intensity ranges you type in the AIPS
terminal window. RMFIT prompts you for 4 numbers for Q and U all on
one line. If you type only 2 numbers, they will be used as the
minimum and maximum plot value in both Q and U. To have different
plot ranges, enter 4 numbers where the first number must be less than
the second number and the third number must be less than the fourth.
If they are not, then the plot(s) revert to self-scaling. Then RMFIT
prompts you for 4 more numbers for total polarization and angle. If
you type only two, then the angle plot will be self-scaling.
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SHOW Q&U
Selecting this option changes the plot from total polarization =
sqrt (Q*Q+U*U) and polarization angle = atan2(U,Q) / 2 to Q and U.
The "initial guess" that is plotted is in fact the current solution
rather than the initial guess. Initial guesses plotted in later pixels
are just that however. The plots remain in Q&U for each spectrum fit
until the option SHOW A&P is selected.
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SHOW P&A
Selecting this option changes the plot from Q and U to total
polarization = sqrt (Q*Q+U*U) and polarization angle = atan2(U,Q) / 2.
The "initial guess" that is plotted is in fact the current solution
rather than the initial guess. Initial guesses plotted in later pixels
are just that however. The plots remain in P&A for each spectrum fit
until the option SHOW Q&U is selected.
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