A.1 Data input

A.2 Data output

A.3 Display commands

A.4 Wavelength calibration

A.5 B-star calibration

A.6 Arithmetic operations

A.7 Flat fields

A.8 Data manipulation

A.9 Aperture photometry

A.10 Line analysis

A.11 S-distortion and échelle order straightening

A.12 Fudging data

A.13 Examining data

A.14 Slicing through images and cubes

A.15 Fibre data

A.16 Flux calibration

A.17 Extinction

A.18 Complex data and FFTs

A.19 Infra-red data

A.20 Échelle data

A.21 Spectroscopy Data Reduction (Specdre)

A.22 Spectroscopy Data Reduction (Twodspec)

A.23 Miscellany

A.2 Data output

A.3 Display commands

A.4 Wavelength calibration

A.5 B-star calibration

A.6 Arithmetic operations

A.7 Flat fields

A.8 Data manipulation

A.9 Aperture photometry

A.10 Line analysis

A.11 S-distortion and échelle order straightening

A.12 Fudging data

A.13 Examining data

A.14 Slicing through images and cubes

A.15 Fibre data

A.16 Flux calibration

A.17 Extinction

A.18 Complex data and FFTs

A.19 Infra-red data

A.20 Échelle data

A.21 Spectroscopy Data Reduction (Specdre)

A.22 Spectroscopy Data Reduction (Twodspec)

A.23 Miscellany

ALASIN — Read a spectrum in ALAS (Abs. Line Analysis System) format

FITSET — Set the value of a FITS keyword

FITSKEYS — List the FITS keywords in a data file

ICOR16 — Corrects 16 bit data from signed to unsigned range

RCGS2 — Reads UKIRT CGS2 spectrum (also UKT9 and UKT6 CVF)

RDFITS — Read file in AAO de facto ‘Disk FITS’ format

RDIPSO — Read file in DIPSO/IUEDR/SPECTRUM format

TABLE — List contents of a SPICA memory file

ALASOUT — Output a spectrum in ALAS (Abs. Line Analysis System) format

WDFITS — Writes an image out in the AAO de facto ’Disk FITS’ format

WDIPSO — Writes a file in DIPSO/IUEDR/SPECTRUM format

CCUR — After SPLOT, uses graphics cursor to indicate data values

COLOUR — Set colour table for image display

DVDPLOT — Plot the data in one file against the data in another

ELSPLOT — Produces a long ($<$3m)
error bar plot of a spectrum

ESPLOT — Produces an error bar plot of a spectrum

HARD — Sets the file name for hard copy output

HOPT — Histogram optimisation of an image

ICONT — Produces a contour map of an image

ICUR — Inspect an image with cursor

IDEV — Set the device for image display

IGCUR — Use cursor to show x, y and data values

IGREY — Produces a grey-scale plot of an image

IMAGE — Display an image on the selected image display

IPLOTS — Plots successive cross-sections of an image, several to a page

ISPLOT — Plots successive cross-sections through an image

LSPLOT — Hardcopy spectrum plot of specified size (up to 3 metres)

MSPLOT — Plots a long spectrum as a series of separate plots

SOFT — Sets the device/type for terminal graphics

SPLOT — Plots a spectrum

XCUR — Uses cursor to delimit part of a spectrum

ARC — Interactive manual arc line identification

ECHARC — Fit an échelle arc

EMLT — Fits gaussians to the strongest lines in a spectrum

FSCRUNCH — Rebin data with a disjoint wavelength coverage to a linear one

IARC — Given fit to single spectrum, fit all spectra in a 2-D arc

ISCRUNCH — Rebin an image to linear wavelength scale given IARC results

ISCRUNI — Like ISCRUNCH, but interpolates between two IARC result sets

LXSET — Set X array of spectrum/image to specified range

SCRUNCH — Rebin a spectrum to a linear wavelength range

VACHEL — Air to vacuum, and/or recession velocity wavelength conversion

XCOPI — Like XCOPY but interpolates X-data from 2 files

XCOPY — Copy X-info (eg wavelengths) into a spectrum

BSMULT — Atmospheric band removal using a B-star calibration spectrum

CFIT — Generate a spectrum using the cursor

CSET — Interactively set regions of a spectrum to a constant value

MASK — Generate a mask spectrum given a spectrum and a mask table

MCFIT — Fit a continuum to a spectrum, given a mask spectrum

NCSET — Set a region of a spectrum to a constant

CLIP — Clip data above and below a pair of threshold values

IADD — Adds two images (or two spectra)

IALOG — Takes the antilog of an image

ICADD — Adds a constant to an image

ICDIV — Divides an image by a constant

ICMULT — Multiplies an image by a constant

ICONV3 — Convolve an image with a 3x3 convolution kernel

ICSUB — Subtracts a constant from an image

IDIFF — Takes the ’differential’ of an image

IDIV — Divides two images (or two spectra)

IGCONV — Convolve an image with a specified filter

ILOG — Takes the logarithm of an image

IMULT — Multiplies two images (or two spectra)

IPOWER — Raises an image to a specified power

IREVX — Reverse an image (or spectrum) in the X-direction

IREVY — Reverse an image in the Y-direction

ISHIFT — Applies a linear x and a linear y shift to an image

ISMOOTH — 2-D smooth of image using 9-point smoothing algorithm

ISTRETCH — Stretches and shifts an image in X and Y.

ISUB — Subtracts two images (or two spectra)

ISUBSET — Produces a subset of an image

ISUPER — Produces a superset of an image

ISXADD — Adds a spectrum to each X direction x-section of an image

ISXDIV — Divides a spectrum into each X direction x-section of an image

ISXMUL — Multiplies each X direction image x-sect by a spectrum

ISXSUB — Subtracts a spectrum from each X direction x-section of an image

ISYADD — Adds a spectrum to each Y direction x-section of an image

ISYDIV — Divides a spectrum into each Y direction x-section of an image

ISYMUL — Multiplies each Y direction image x-sect by a spectrum

ISYSUB — Subtracts a spectrum from each Y direction x-section of an image

IXSMOOTH — Smooth in x-direction by gaussian convolution

RESAMPLE — Rebin an image to different dimensions and/or orientation

RESCALE — Rescale using user-defined upper and lower limits

ROTX — Rotate data along the X-axis

CFIT — Generate a spectrum using the cursor

FF — Flat field an image (uses JT’s algorithm)

FFCROSS — Cross-correlate an image and a flat field (mainly IPCS data)

MASK — Generate a mask spectrum given a spectrum and a mask table

MCFIT — Fit a continuum to a spectrum, given a mask spectrum

ISXDIV — Divides a spectrum into each X direction x-section of an image

ADJOIN — Append two spectra (strictly a merge by wavelength value)

BCLEAN — Automatic removal of bad lines and cosmic rays from CCD data

CFIT — Generate a spectrum using the cursor

CLEAN — Interactive patching of bad lines, bad pixels in an image

COADD — Form the spectrum which is the mean of the rows in an image

COMBINE — Combine two spectra, adding with weights according to errors

COSREJ — Reject cosmic rays from a set of supposedly identical spectra

CREOBJ — Create a data object or file

FSCRUNCH — Rebin data with a disjoint wavelength coverage to a linear one

HCROSS — Cross-correlate two spectra amp get redshift and error

HIST — Produce histogram of data value distribution in an image

HOPT — Histogram optimisation of an image

ICONV3 — Convolve an image with a 3x3 convolution kernel

ICOR16 — Corrects 16 bit data from signed to unsigned range

IDIFF — Takes the ’differential’ of an image

IGCONV — Convolve an image with a specified filter

IREVX — Reverse an image (or spectrum) in the X-direction

IREVY — Reverse an image in the Y-direction

IROT90 — Rotates an image through 90 degrees

MEDFILT — Applies a square median filter to an image

MEDFILTR — Applies a rectangular median filter to an image

MEDSKY — Take the median of a number of images

POLYSKY — Fits and subtracts sky from a long slit spectrum

SCLEAN — Interactive patching of images, especially SCUBA data

SCNSKY — Calculates a sky spectrum for a scanned CCD image

SCROSS — Cross-correlate two spectra and get relative shift

SCRUNCH — Rebin a spectrum to a linear wavelength range

SFIT — Fit a polynomial to a spectrum

APERTURE — Do simple minded aperture photometry on a series of frames

CENTERS — Generate file of object centroids from ICUR/IGCUR output

FOTO — Perform aperture photometry given CENTERS output

ICUR — Inspect an image with cursor

IGCUR — Use cursor to show x, y and data values

ABLINE — Interactive absorption line analysis

EMLT — Fits gaussians to the strongest lines in a spectrum

GAUSS — Interactive fit of Gaussians to emission or absorption lines

CDIST — S-distortion correction using SDIST results

FINDSP — Locate fibre spectra in an image

ICUR — Inspect an image with cursor

IGCUR — Use cursor to show x, y and data values

OFFDIST — Applies an offset to an SDIST fit

OVERPF — Overlays a FINDSP fit on another image

POLEXT — Extract fibre spectra from an image after a FINDSP analysis

SDIST — Analyse an image containing spectra for S-distortion

COPOBJ — Copy an HDS object

CREOBJ — Create a data object or file

CSET — Interactively set regions of a spectrum to a constant value

DELOBJ — Delete a data object or a file

FLAG2QUAL — Converts ‘flagged’ values to produce a quality array

GOODVAR — Replace negative, zero and bad variance values

ICSET — Set a selected region of an image to a constant value

ISEDIT — Allows interactive editing of a 1-D or 2-D spectrum

LXSET — Set X array of spectrum/image to specified range

LYSET — Set Y array of spectrum/image to specified range

NCSET — Set a region of a spectrum to a constant

Q2BAD — Converts an NDF’s quality into bad values

QUAL2FLAG — Converts a quality array into ‘flagged’ values

REMBAD — Removes pixels that have been flagged as bad from data

RENOBJ — Change the name or location of an object within an HDS file

SETOBJ — Assign value to an HDS primitive

SPIED — Interactive spiketrum editor

TIPPEX — Modify individual pixel values with cursor

XCADD — Adds a constant to the X data in a file

XCDIV — Divides the X data in a file by a constant

XCMULT — Multiplies the X data in a file by a constant

XCSUB — Subtracts a constant from the X data in a file

YCADD — Adds a constant to the Y data in a file

YCDIV — Divides the Y data in a file by a constant

YCMULT — Multiplies the Y data in a file by a constant

YCSUB — Subtracts a constant from the Y data in a file

HIST — Produce histogram of data value distribution in an image

FIGINFO — Describes the contents of a Figaro data file

FITSKEYS — List the FITS keywords in a data file

ICUR — Inspect an image with cursor

IGCUR — Use cursor to show x, y and data values

ILIST — List the data in an image (or spectrum)

ISTAT — Provides some statistics about an image (max, min etc.)

EXTLIST — Adds a number of non-contiguous lines of an image
-$>$ a
spectrum

EXTRACT — Adds contiguous lines of an image
-$>$ a
spectrum

GROWX — Performs reverse function to that of EXTRACT

GROWXT — Copies an image into contiguous XT planes of a cube

GROWXY — Copies an image into contiguous XY planes of a cube

GROWY — Performs reverse function to that of YSTRACT

GROWYT — Copies an image into contiguous YT planes of a cube

OPTEXTRACT — Extracts a long slit spectrum using Horne’s optimal extraction

PROFILE — Determines a long slit spectrum profile for use by OPTEXTRACT

SLICE — Takes a slice with arbitrary end points through an image

XTPLANE — Adds contiguous XT planes of a data cube
-$>$ an
image

XYPLANE — Adds contiguous XY planes of a data cube
-$>$ an
image

YSTRACT — Adds contiguous columns of an image
-$>$ a
spectrum

YTPLANE — Adds contiguous YT planes of a data cube
-$>$ an
image

FINDSP — Locate fibre spectra in an image

OVERPF — Overlays a FINDSP fit on another image

POLEXT — Extract fibre spectra from an image after a FINDSP analysis

ABCONV — Convert spectrum from Janskys into AB magnitudes

CALDIV — Generate calibration spectrum from continuum standard spectra

CFIT — Generate a spectrum using the cursor

CSET — Interactively set regions of a spectrum to a constant value

CSPIKE — Create calibration spiketrum given spiketrum and standard spectrum

FIGSFLUX — Flux calibrates a FIGS spectrum

FLCONV — Convert a spectrum in Janskys into one in erg/s/cm**2/Angstrom

FWCONV — General unit conversion for spectra

GSPIKE — Generates a ’spiketrum’ from a table of values

INTERP — Interpolates between the points of a ’spiketrum’
-$>$ a
spectrum

IRFLUX — Flux calibrates an IR spectrum using a black-body model

LINTERP — Linear interpolation between spiketrum points
-$>$
spectrum

NCSET — Set a region of a spectrum to a constant

SFIT — Fit a polynomial to a spectrum

SPFLUX — Applies a flux calibration spectrum to an observed spectrum

SPIED — Interactive spiketrum editor

SPIFIT — Fits a global polynomial to a spiketrum
-$>$ a
spectrum

EXTIN — Correct spectrum for atmospheric extinction

GSPIKE — Generates a ’spiketrum’ from a table of values

LINTERP — Linear interpolation between spiketrum points
-$>$
spectrum

BFFT — Takes the reverse FFT of a complex data structure

CMPLX2I — Extracts the imaginary part of a complex data structure

CMPLX2M — Extracts the modulus of a complex data structure

CMPLX2R — Extracts the real part of a complex data structure

CMPLXADD — Add two complex structures

CMPLXCONJ — Produce the complex conjugate of a complex structure

CMPLXDIV — Divide two complex structures

CMPLXFILT — Create a mid-pass filter for complex data

CMPLXMULT — Multiply two complex structures

CMPLXSUB — Subtract two complex structures

COSBELL — Create data that goes to zero at the edges in a cosine bell

FFT — Takes the forward FFT of a complex data structure

I2CMPLX — Copies an array into the imaginary part of a complex structure

PEAK — Determines position of highest peak in a spectrum

R2CMPLX — Creates a complex data structure from a real data array

ROTX — Rotate data along the X-axis

FET321 — Extracts a spectrum from 1 detector from etalon mode FIGS data

FIGS321 — Processes a FIGS data cube down to a single spectrum

FIGS322 — Processes a FIGS data cube down to an image

FIGS422 — Process a FIGS image-mode hypercube down to an image

FIGS423 — Process a FIGS image-mode hypercube down to a cube

FIGS424 — Sort a FIGS image-mode hypercube into wavelength order

FIGSEE — Generate a seeing ripple spectrum from a FIGS spectrum

FIGSFLUX — Flux calibrates a FIGS spectrum

IRCONV — Converts data in Janskys to W/m**2/um

IRFLAT — Generates a ripple spectrum from an IR spectrum

IRFLUX — Flux calibrates an IR spectrum using a black-body model

REMBAD — Removes pixels that have been flagged as bad from data

CDIST — S-distortion correction using SDIST results

ECHARC — Fit an échelle arc

ECHFIND — Locate spectra in échelle data

ECHMASK — Produce an extraction mask from an SDIST analysis

ECHMERGE — Merge échelle spectra into a single long spectrum

ECHSELECT — Interactive selection of sky and object spectra for an échelle

ICUR — Inspect an image with cursor

IGCUR — Use cursor to show x, y and data values

IMAGE — Display an image on the selected image display

MASKEXT — Extracts échelle orders using a mask created by ECHMASK

OFFDIST — Applies an offset to an SDIST fit

SDIST — Analyse an image containing spectra for S-distortion

**Input/output**

ASCIN — Read a 1-D or N-D data set from an ASCII table.

ASCOUT — Write an NDF to an ASCII table.

**Display**

MOVIE — Browse through slices of a cube.

SPECCONT — Contour a two-dimensional cut.

SPECGRID — Plot spectra on position grid.

SPECPLOT — Plot a spectrum.

**Statistics, fitting**

CORREL — Correlate two or three data sets.

EVALFIT — Evaluate fit results.

FITBB — Fit diluted Planck curves to a spectrum.

FITGAUSS — Fit Gauss profiles to a spectrum.

FITPOLY — Fit a polynomial to a spectrum.

FITTRI — Fit triangular profiles to a spectrum.

MOMENTS — Calculate moments of spectra in a cube.

**Axis calibration**

ARCDISP — Fit polynomial dispersion curve.

ARCGENDB — Convert list of laboratory values to feature data base.

ARCIDENT — Auto-identify located features.

ARCLOCAT — Locate line features in a set of spectra.

**Data calibration**

BBODY — Calculate a black body spectrum.

**Convolution, re-sampling, merging**

FILLCUBE — Copy one NDF into part of another.

RESAMP — Re-sample and average several spectra.

**Reshaping**

GROW — Copy an N-dimensional cube into part of an (N+M)-dimensional one.

SUBSET — Take a subset of a data set.

XTRACT — Average an N-dimensional cube into an (N-M)-dimensional one.

**Miscellaneous**

EDITEXT — Edit the Specdre Extension.

**Display**

ISCAN — Plots cut through a 2D longslit array.

HIMAGE — Plots a greyscale image of a 2D array.

CSCAN — Plot array of profiles from a 3D array.

**Axis Calibration**

ARC2D — Calibrates distortions in 2D arc line data.

COMB — Corrects for S-distortion using continua.

ARCSDI — Corrects for arc line curvature.

**Line Profile Analysis**

LONGSLIT — Fits 2D longslit arrays and plots results.

FIBDISP — Fits 3D cubes and plots results.

**Data Manipulation**

FITCONT — Fit continuum for subtraction.

CSUB — Subtract fitted continuum.

CADD — Add back fitted continuum.

**Miscellaneous**

FIBSEP — Seperate spectra in 2D array.

FIB2CUBE — Stack LONGSLIT results into a data cube.

CUBE2LONG — Extract fits from a cube in LONGSLIT format.

VIG — Corrects a 2D array for vignetting.

CRIGAUSS — Generates an NDF with a multiple gaussian profile.

CHANGED — Lists differences between fits in two files.

CCDLIN — Applies a linearity correction to AAO CCD data

ERRCON — Converts percentage error values to absolute values

FIGHELP — Browse through the Figaro help library

RETYPE — Changes the type of the main data array in a file

SQRTERR — Generates an error array as Error = Square Root of (Data/Const)

TRIMFILE — Creates a copy of an HDS file without unused space