AIPS NRAO AIPS HELP file for BLC in 31DEC24



As of Sat Oct 5 17:07:01 2024



HELP SECTION

BLC
Type: Adverb (Real array, 7 elements)
Use:  The array subscripts of the pixel at the Bottom Left Corner of the
      desired subarray of the image.  The first value in BLC gives the
      column number of the pixel; the second value in BLC gives the row
      number of the pixel.  The array may contain up to 7 dimensions.
Null value: 7*0
      Null value is usually assigned to (1,1,...), the bottom left
      corner of the entire image.
Verbs:
   COWINDOW......Set a window based on coordinates.
   IMCENTER......Returns pixel position of sub-image centroid.
   IMSTAT........Returns statistics of a sub-image.
   MFITSET.......Gets adverbs for running IMFIT and JMFIT.
   SETSLICE......Set slice end points on the TV interactively.
   TVWINDOW......Set a window on the TV with the cursor.
Procedures:
   DOFARS........Procedure to aid in Faraday rotation synthesis using the
                 FARS task.
   IMFRING.......Large image delay fitting with IM2CC and OOFRING.
   IMSCAL........Large image self-cal with IM2CC and OOCAL.
   SETXWIN.......Procedure to set BLC and TRC with TV cursor.
   TKWIN.........Procedure to set BLC and TRC with Graphics cursor.
Tasks:
   AFARS.........Is used after FARS to determine Position and Value of the
                 maximum.
   AGAUS.........Fits 1-dimensional Gaussians to absorption-line spectra.
   AHIST.........Task to convert image intensities by adaptive histogram.
   APCLN.........Deconvolves images with CLEAN algorithm.
   BDEPO.........Computes depolarization due to rotation measure
                 gradients.
   BLANK.........Blanks out selected, e.g. non-signal, portions of an
                 image.
   BLCAL.........Compute closure offset corrections.
   BLCHN.........Compute closure offset corrections on a
                 channel-by-channel basis.
   BLSUM.........Sums images over irregular sub-images, displays spectra.
   BLWUP.........Blow up an image by any positive integer factor.
   BSAVG.........Task to do an FFT-weighted sum of beam-switched images.
   BSCLN.........Hogbom Clean on beam-switched difference image.
   BSCOR.........Combines two beam-switched images.
   BSGEO.........Beam-switched Az-El image to RA-Dec image translation.
   CALWR.........Writes calibrator source model images w CC files to FITS
                 disk files.
   CCNTR.........Generate a contour plot file from an image with CC or MF
                 plotted.
   CCRES.........Removes or restores a CC file to a map with a gaussian
                 beam.
   CMPLX.........Combines complex images by a variety of mathematical
                 methods.
   CNTR..........Generate a contour plot file or TV plot from an image.
   COMB..........Combines two images by a variety of mathematical methods.
   CONVL.........Convolves an image with a gaussian or another image.
   CUBIT.........Model a galaxy's density and velocity distribution from
                 full cube.
   DCONV.........Deconvolves a gaussian from an image.
   DSKEW.........Geometric interpolation correction for skew.
   FARS..........Faraday rotation synthesis based on the brightness vs
                 wavelength.
   GAL...........Determine parameters from a velocity field.
   GREYS.........Plots images as contours over multi-level grey.
   HGEOM.........Interpolates image to different gridding and/or geometry.
   HISEQ.........Task to translate image by histogram equalization.
   IM2CC.........Task to convert an image to multi-facet Clean Components.
   IM2UV.........Converts an image to a visibility data set.
   IMCLP.........Clip an image to a specified range.
   IMEAN.........Displays the mean & extrema and plots histogram of an
                 image.
   IMFIT.........Fits Gaussians to portions of an image.
   IMFLT.........Fits and removes a background intensity plane from an
                 image.
   IMLHS.........Converts images to luminosity/hue TV display.
   IMLIN.........Fits and removes continuum emission from cube.
   IMMOD.........Adds images of model objects to an image.
   IMTXT.........Write an image to an external text file.
   IMVIM.........Plots one image's values against another's.
   IRING.........Integrates intensity / flux in rings / ellipses.
   ISPEC.........Plots and prints spectrum of region of a cube.
   JMFIT.........Fits Gaussians to portions of an image.
   KNTR..........Make a contour/grey plot file from an image w multiple
                 panels.
   LAYER.........Task to create an RGB image from multiple images.
   LGEOM.........Regrids images with rotation, shift using interpolation.
   LTESS.........Makes mosaic images by linear combination.
   MARSP.........Check Mars polarization angles
   MATHS.........Operates on an image with a choice of mathematical
                 functions.
   MEDI..........Combines four images by a variety of mathematical
                 methods.
   MOD3D.........Computes a 3D CC model from a set of facets.
   MODIM.........Adds images of model objects to image cubes in IQU
                 polarization.
   MODSP.........Adds images of model objects to image cubes in I/V
                 polarization.
   MOMFT.........Calculates images of moments of a sub-image.
   MOMNT.........Calculates images of moments along x-axis (vel, freq,
                 ch).
   MWFLT.........Applies linear & non-linear filters to images.
   NANS..........Reads an image or a UV data set and looks for NaNs.
   NINER.........Applies various 3x3 area operaters to an image.
   NNLSQ.........Non-Negative-Least-Squares decomposition of spectrum.
   OGEOM.........Simple image rotation, scaling, and translation.
   OHGEO.........Geometric interpolation with correction for 3-D effects.
   PANEL.........Convert HOLOG output to panel adjustment table.
   PASTE.........Pastes a selected subimage of one image into another.
   PBCOR.........Task to apply or correct an image for a primary beam.
   PCNTR.........Generate plot file with contours plus polarization
                 vectors.
   PFPL1.........Paraform Task to generate a plot file: (does grey scale).
   PFPL2.........Paraform Task to generate a plot file: (slice intensity).
   PFPL3.........Paraform Task to generate a plot file: (does histogram).
   PGEOM.........Task to transform an image into polar coordinates.
   PLCUB.........Task to plot intensity vs x panels on grid of y,z pixels.
   PLROW.........Plot intensity of a series of rows with an offset.
   PROFL.........Generates plot file for a profile display.
   PRTIM.........Prints image intensities from an MA catalog entry.
   QUOUT.........Writes text file of Q, U versus frequency to be used by
                 RLDIF.
   REMAG.........Task to replace magic blanks with a user specified value.
   RFARS.........Correct Q/U cubes for Faraday rotation synthesis results.
   RGBMP.........Task to create an RGB image from the 3rd dim of an image.
   RM............Task to calculate rotation measure and magnetic field
   RMFIT.........Fits 1-dimensional polarization spectrum to Q/U cube.
   RMSD..........Calculate rms for each pixel using data in a box around
                 the pixel.
   RSPEC.........Plots and prints spectrum of rms of a cube.
   RSTOR.........Restores a Clean component file to a map with a Gaussian
                 beam.
   SABOX.........Create box file from source islands in facet images.
   SAD...........Finds and fits Gaussians to portions of an image.
   SCLIM.........Operates on an image with a choice of mathematical
                 functions.
   SDCLN.........Deconvolves image by Clark and then "SDI" cleaning
                 methods.
   SERCH.........Finds line signals in transposed data cube.
   SHADW.........Generates the "shadowed" representation of an image.
   SLICE.........Task to make a slice file from an image.
   SMOTH.........Task to smooth a subimage from upto a 7-dim. image.
   SPCOR.........Task to correct an image for a primary beam and spectral
                 index.
   SPFIX.........Makes cube from input to and output from SPIXR spectral
                 index.
   SPIXR.........Fits spectral indexes to each row of an image incl
                 curvature.
   SQASH.........Task to collapse several planes in a cube into one plane
                 or row.
   STACK.........Task to co-add a set of 2-dimensional images with
                 weighting.
   STESS.........Task which finds sensitivity in mosaicing.
   STFND.........Task to find stars in an image and generate an ST table.
   STFUN.........Task to calculate a structure function image.
   SUBIM.........Task to select a subimage from up to a 7-dim. image.
   SUMIM.........Task to sum overlapping, sequentially-numbered images.
   SUMSQ.........Task to sum the squared pixel values of overlapping,.
   TAFFY.........User definable task to operate on an image.
   TRANS.........Task to transpose a subimage of an up to 7-dim. image.
   TVHLD.........Interactive task to load an image to the TV with
                 histogram equalization.
   TVIEW.........Display image cube in all 3 transpositions with rotation
                 & reference.
   TVRGB.........Make TV image from images of true color (RGB) images.
   TVSAD.........Finds and fits Gaussians to portions of an image with
                 interaction.
   UNSPX.........Removes spectral index model from a data cube.
   UTESS.........Deconvolves images by maximizing emptiness.
   VTESS.........Deconvolves sets of images by the Maximum Entropy Method.
   WARP..........Model warps in Galaxies.
   WTSUM.........Task to do a a sum of images weighted by other images.
   XBASL.........Fits and subtracts nth-order baselines from cube (x
                 axis).
   XGAUS.........Fits 1-dimensional Gaussians to images: restartable.
   XMOM..........Fits one-dimensional moments to each row of an image.
   XPLOT.........Plots image rows one at a time on the graphics or TV
                 screen.
   XSMTH.........Smooth data along the x axis.
   XSUM..........Sum or average images on the x axis.
   XTRAN.........Create an image with transformed coordinates.
   ZAMAN.........Fits 1-dimensional Zeeman model to absorption-line data.
   ZEMAN.........Fits 1-dimensional Zeeman model to data.

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