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Last modified: 26 October 2010

Contextual List of Ahelp Files


ahelp calibration chandra ciao_contrib concept contrib dm group gui modules paramio pixlib proposaltools py.ciao_contrib py.contrib py.crates py.crates_contrib py.transform region scripting sherpa_tools sl.ciao_contrib sl.contrib sl.crates sl.crates_contrib sl.transform slang stackio tools

Context Topic Summary
ahelp ahelp Access the CIAO help documentation.

calibration ardlib Analysis Reference Data Library
caldb CALibration DataBase (CALDB)

chandra coords Coordinate systems used in Chandra analysis
eventdef Column definition in Chandra event files
level Describes the amount of processing performed to create a given product.
mtl A description of the Mission Time Line (MTL)
pileup An overview of pileup in the Chandra ACIS detector.
times "Times" used in Chandra datasets and Chandra data analysis

ciao_contrib chandra_repro Reprocess a Chandra dataset

concept autoname Autonaming is a feature available in various tools for automatically naming an output file based upon the name of an input file.
ciaorc The .ciaorc file provides user-configuration options for CIAO
ciao Chandra Interactive Analysis of Observations
merging_rules A description of the merging rules used when combining header information.
parameter Describes the parameter interface used by CIAO.
stack How to set a parameter to more than one value using a stack.
subspace Describes the filtering applied to a file

contrib combine_spectra Combine multiple PHA imaging spectra and associated ARF responses

dm dmascii Using the Data Model with text files
dmbinning The CIAO binning syntax
dmfiltering Filtering tables and images with the Data Model
dmopt Controlling Data Model internal options
dmregions CIAO region filtering syntax
dm CIAO Data Model: syntax for filtering and binning files

group grpAdaptiveSnr Adaptively group an array by signal to noise.
grpAdaptive Group an array by the number of counts per group using an adaptive scheme.
grpBinFile Group an array using the grouping applied to another dataset.
grpBinWidth Group an array into a set of equal-width groups (by group width).
grpBin Group an array using low and high boundaries.
grpGetChansPerGroup Calculate the number of channels (elements) in each group.
grpGetGroupSum Apply the supplied grouping to an array.
grpGetGrpNum Calculate the group number for each element in the array.
grpMaxSlope Group an array so that its absolute gradient is above a user-defined limit.
grpMinSlope Group an array so that its absolute gradient is below a user-defined limit.
grpNumBins Group an array into a set of equal-width groups (by number of groups).
grpNumCounts Group an array by the number of counts per group.
grpSnr Group an array by signal to noise.

gui analysis-menu Run commands from the "Analysis" menu in CIAO GUIs
gui Graphical User Interface (GUI)
peg PEG: the parameter editor GUI (for CXCDS parameter interface)
prism Format-independent file browsing GUI
taskmonitor GUI to run a task as a background process and display the output

modules group_slang The S-Lang interface to the CXC grouping library
paramio The S-Lang interface to the CXC parameter system
pixlib The S-Lang interface to the CXC pixlib library
region The S-Lang interface to the CXC region library
stackio The S-Lang interface to the CXC stack library

paramio paccess Returns the path to the specified parameter file.
paramclose Close a parameter file opened by paramopen.
paramopen Open a parameter file.
pgets Read/write individual parameter values from S-Lang.
pget Get a parameter value within S-Lang.
plist_names List parameter names for a single tool from S-Lang.
pquery Query a parameter value from S-Lang.
pset Set a parameter value within S-Lang.
punlearn Restore the system defaults for a parameter file from S-Lang.

pixlib pix_apply_aspect Convert from FPC to Sky tangent coordinates by applying an aspect solution.
pix_chip_to_fpc Convert from the Chip to Focal Plane coordinate (FPC) system.
pix_chip_to_gdp Convert from the Chip to Grating Dispersion Plane (GDP) coordinate system.
pix_chip_to_tdet Convert from the Chip to Tiled Detector (TDET) coordinate system.
pix_close_pixlib Convert between different Chandra coordinate systems in S-Lang
pix_deapply_aspect Convert from Sky tangent coordinates to FPC by reversing the aspect solution.
pix_disp_config Display the current settings of the pixlib module.
pix_dmTanPixToWorld Convert from FPC to World (celestial) coordinates by applying an aspect solution.
pix_dmTanWorldToPix Convert from World (celestial) to FPC coordinates by applying an aspect solution.
pix_fpc_to_chip Convert from the Focal Plane (FPC) to Chip coordinate system.
pix_fpc_to_gdp Convert from the Focal Plane (FPC) to Grating Dispersion Plane (GDP) coordinate system.
pix_fpc_to_msc Convert from the Focal Plane (FPC) to Mirror Spherical (MSC) coordinate system.
pix_gac_to_gdp Convert from the Grating diffracted Angular coordinates (GAC) to Grating Dispersion Plane (GDP) coordinate system.
pix_gdp_to_gac Convert from the Grating Dispersion Plane (GDP) to Grating diffracted Angular coordinates (GAC) system.
pix_get_energy Return the photon energy corresponding to a given grating dispersion (GAC) value.
pix_get_flength Return the value of the telescope focal length used by the pixlib module.
pix_get_fp_scale_in_asec Returns the pixel size in arcsec for the current detector
pix_get_grating_angle Return the grating angle of the currently-selected grating arm.
pix_get_grating_period Return the grating period of the currently-selected grating arm.
pix_get_grating_wavelength Return the photon wavelength corresponding to a given grating dispersion (GAC) value.
pix_get_rowland Return the value of the Rowland Circle diameter used by the pixlib module.
pix_init_pixlib Initialize the pixlib library.
pix_set_aimpoint Set the aim point to be used by the pixlib module.
pix_set_detector Set the detector to use in the pixlib routines.
pix_set_fpsys Set the focal plane system for the pixlib module.
pix_set_gdpsys Set the grating dispersion plane (GDP) system for the pixlib module.
pix_set_grating Set the grating arm and order to use in the pixlib module.
pix_set_gzo Set the grating zero-order position for the pixlib module.
pix_set_simoffset Set the stage position for the pixlib module.
pix_set_tdetsys Set the tiled detector plane system for the pixlib module.
pix_tdet_to_chip Convert from the Tiled Detector (TDET) to Chip coordinate system.

proposaltools colden COLDEN is an interactive program to evaluate the neutral hydrogen column density at a given direction on the sky
dates DATES is an interactive calendar and time conversion tool.
obsvis ObsVis is the Observation Visualizer created at the Chandra Science Center in Cambridge Massachusetts, USA.
pimms PIMMS (Portable, Interactive Multi-Mission Simulator) converts source fluxes and count rates between missions.
precess PRECESS is an interactive astronomical coordinate conversion program. It provides precession of equatorial coordinates and conversion between equatorial, ecliptic, galactic, and supergalactic coordinates.
prop-coords Defines available coordinate systems for Chandra Proposal Tools
prop-time Defines available calendars and timescales for command line versions of Chandra Proposal Tools
prop-tools Tools that aid in the preparation and submission of Chandra proposals

py.ciao_contrib check_caldb_version Check whether the locally-installed version of the Chandra Calibration DataBase (CALDB) is up to date
ciao_caldb Utility routines for the CIAO CALDB (CIAO contributed package).
ciao_contrib Contributed Crates and Sherpa routines for CIAO.
ciao_runtool Run CIAO tools from Python as if they were functions (CIAO contributed package).
ciao_smooth Simple smoothing routines for 2D data
ciao_utils Utility routines for CIAO (CIAO contributed package).
get_caldb Access various information about the Chandra Calibration DataBase (CALDB)
simple_hist Create a one-dimensional histogram of a data array
simple_stats Calculate several basic statistic values for a data array

py.contrib lc_clean lc_clean - remove periods of high (or low) count rates using the same technique as the ACIS background files
lc_sigma_clip lc_sigma_clip - remove flares from a light curve using an iterative sigma-clipping algorithm (used to be called analyze_ltcrv)
lightcurves lightcurves - routines to remove periods of anomalously high (or low) count rates in a lightcurve

py.crates add_col Add a column to a crate.
add_key Add a keyword to a crate.
add_piximg Add an image to a crate.
col_exists Determine if a column exists in a crate.
copy_colvals Copy the column values from a crate.
copy_piximgvals Copy the image values from a crate.
cratedata CrateData object types in the CRATES library.
crates CRATES - A high-level I/O interface for Python
delete_col Delete a column from a crate.
delete_key Delete a keyword from a crate.
delete_piximg Delete an image from a crate.
get_axis_transform Return the axis transform from an IMAGECrate.
get_colvals Get the column values from a crate.
get_col_names Return an array of the column names in a crate.
get_col Return a CrateData object of a column from a crate.
get_crate_item_type Return the type of the crate item as a string.
get_crate_type Return the type of the crate as a string.
get_keyval Return the value of a keyword in a crate.
get_key_names Return an array of the keywords in a crate.
get_key Return a CrateKey object of a keyword from a crate.
get_number_cols Return the number of columns in a crate.
get_number_rows Return the number of rows in a crate.
get_piximgvals Return the values from an image crate.
get_piximg_shape Return the dimension array describing the image shape.
get_piximg Return a CrateData object of an image from a crate.
get_transform_matrix Extract the transform matrix from a crate.
get_transform Extract the transform from a crate.
is_arf Determine if the crate contains an ARF.
is_pha Determine if the crate contains a PHA file.
is_rmf Determine if the crate contains an RMF.
is_virtual Determine if the input column from the crate is a virtual column.
key_exists Determine if the keyword exists in the crate.
print_axis_names Display the names of the axes in an image.
print_col_names Display the names of the columns in a crate.
print_key_names Display the names of the keywords in a crate.
read_arf Load an ARF file into an ARFCrate.
read_file Read FITS or ASCII data into a crate.
read_pha Load a PHA file into a PHACrate.
read_rmf Load an RMF file into an RMFCrate.
set_colvals Set the values of a column in a crate.
set_keyval Set the keyword value in a crate.
set_piximgvals Set the image values in a data array.
write_arf Write an ARFCrate to an output file.
write_file Write a crate to an output file.
write_pha Write a PHACrate to an output file.
write_rmf Write an RMFCrate to an output file.

py.crates_contrib crates_contrib Contributed CIAO routines for Crates.
crates_utils Utility routines for Crates (CIAO contributed package)
make_table_crate Create a TABLE Crate from a set of arrays (columns).
scale_image_crate Scale the pixel values in an IMAGE crate (useful for add_image)
smooth_image_crate Smooth the pixel values in an IMAGE crate (useful for add_image)
write_arrays Write arrays to an ASCII file
write_columns Write out arrays (columns) to a file as a table (ASCII or FITS format).

py.transform apply_transform Apply a transform to the given data.
copy_transform Copy the transform.
get_transform_type Return the flavor of the input Transform object.
transform TRANSFORMS - A high-level interface for the Transform library

region regArea Calculate the area enclosed by a region.
regExtent Calculate the bounding box of a region.
regInsideRegion Is a point (or set of points) inside a region?
regParse Parse a region for use by the routines in the region library
regPrintRegion Print out details about a region.
regRegionString Print out details about a region.

scripting python Python is a dynamic object-oriented programming language

sherpa_tools modelflux Calculate model flux or count rate
srcextent Determine if a source is extended within a confidence interval.

sl.ciao_contrib ciao_contrib Contributed Crates and Sherpa routines for CIAO.
ciao_utils Utility routines for CIAO (CIAO contributed package).
simple_hist Create a one-dimensional histogram of a data array
simple_stats Calculate several basic statistic values for a data array

sl.contrib lc_clean lc_clean - remove periods of high (or low) count rates using the same technique as the ACIS background files
lc_sigma_clip lc_sigma_clip - remove flares from a light curve using an iterative sigma-clipping algorithm (used to be called analyze_ltcrv)
lightcurves lightcurves - routines to remove periods of anomalously high (or low) count rates in a lightcurve

sl.crates add_col Add a column to a crate.
add_key Add a keyword to a crate.
add_piximg Add an image to a crate.
col_exists Determine if a column exists in a crate.
copy_colvals Copy the column values from a crate.
copy_piximgvals Copy the image values from a crate.
cratedata CrateData object types in the CRATES library.
crates CRATES - A high-level I/O interface for S-Lang
delete_col Delete a column from a crate.
delete_key Delete a keyword from a crate.
delete_piximg Delete an image from a crate.
get_axis_transform Return the axis transform from an IMAGECrate.
get_colvals Get the column values from a crate.
get_col_names Return an array of the column names in a crate.
get_col Return a CrateData object of a column from a crate.
get_crate_item_type Return the type of the crate item as a string.
get_crate_type Return the type of the crate as a string.
get_keyval Return the value of a keyword in a crate.
get_key_names Return an array of the keywords in a crate.
get_key Return a CrateKey object of a keyword from a crate.
get_number_cols Return the number of columns in a crate.
get_number_rows Return the number of rows in a crate.
get_piximgvals Return the values from an image crate.
get_piximg_shape Return the dimension array describing the image shape.
get_piximg Return a CrateData object of an image from a crate.
get_transform_matrix Extract the transform matrix from a crate.
get_transform Extract the transform from a crate.
is_arf Determine if the crate contains an ARF.
is_pha Determine if the crate contains a PHA file.
is_rmf Determine if the crate contains an RMF.
is_virtual Determine if the input column from the crate is a virtual column.
key_exists Determine if the keyword exists in the crate.
print_axis_names Display the names of the axes in an image.
print_col_names Display the names of the columns in a crate.
print_key_names Display the names of the keywords in a crate.
read_arf Load an ARF file into an ARFCrate.
read_file Read FITS or ASCII data into a crate.
read_pha Load a PHA file into a PHACrate.
read_rmf Load an RMF file into an RMFCrate.
set_colvals Set the values of a column in a crate.
set_keyval Set the keyword value in a crate.
set_piximgvals Set the image values in a data array.
write_arf Write an ARFCrate to an output file.
write_file Write a crate to an output file.
write_pha Write a PHACrate to an output file.
write_rmf Write an RMFCrate to an output file.

sl.crates_contrib crates_contrib Contributed CIAO routines for Crates.
crates_utils Utility routines for Crates (CIAO contributed package)
make_table_crate Create a TABLE Crate from a set of arrays (columns).
scale_image_crate Scale the pixel values in an IMAGE crate (useful for add_image)
write_arrays Write arrays to an ASCII file
write_columns Write out arrays (columns) to a file as a table (ASCII or FITS format).

sl.transform apply_transform Apply a transform to the given data.
copy_transform Copy the transform.
get_transform_type Return the flavor of the input Transform object.
transform TRANSFORMS - A high-level interface for the Transform library

slang slang The S-Lang programing language
slsh Evaluate and run S-Lang code.

stackio stk_append Add an item (or items) to a stack.
stk_build Build a stack from text input (file name or regular expression).
stk_change_current Change the current element of a stack.
stk_change_num Change the given element of a stack.
stk_close Close a stack.
stk_count Returns the number of elements in a stack.
stk_current Returns the current position of the stack.
stk_delete_current Deletes the current element from the stack.
stk_delete_num Deletes the specified element from the stack.
stk_disp Display the contents of a stack.
stk_expand_n Create a numbered stack of N elements.
stk_read_next Returns the next element from a stack.
stk_read_num Returns the selected element from a stack.
stk_rewind Rewind the stack to its starting position.
stk_set_current Sets the current position of the stack.

tools acisreadcorr Flag and relocate out-of-time CCD events
acisspec Coadd ACIS spectra and build weighted ARFs and RMFs.
acis_bkgrnd_lookup Find the matching ACIS "blank-sky" dataset for an observation
acis_build_badpix Create an observation-specific bad-pixel file
acis_classify_hotpix Determine whether a suspicious pixel is hot or affected by an afterglow.
acis_detect_afterglow Identify and flag cosmic ray afterglows
acis_fef_lookup Find the FITS Embedded Function file for use by mkrmf
acis_find_hotpix Identify pixels that have an unusually large (or small) number of events.
acis_process_events Produce or update TIME, coordinates, PI, GRADE, and STATUS information in ACIS event files
acis_run_hotpix Identify and flag "hot" pixels and cosmic-ray "afterglows."
acis_set_ardlib Sets the bad pixel parameters of the ardlib file to the given file
acis_streak_map Generate high frequency background maps (streakmaps) which identify ACIS streaks caused when bright source photons are applied to the wrong pixel during readout.
aconvolve Convolve an N-dimensional image with a kernel
acrosscorr Cross-correlate two N-dimensional images or autocorrelate an image
add_grating_orders Add positive and negative diffraction orders of a grating PHA spectra and the corresponding ARFs
add_grating_spectra Add two, source and background, grating PHA spectra, averages the corresponding ARFs, and group the coadded spectrum.
apowerspectrum Compute the power spectrum of an N-dimensional input array, or from two columns (independent/dependent variable) in an input file
aprates Compute net counts, rate, and/or flux, plus confidence regions, for a point source, using data obtained from source and background apertures in event lists, images, and exposure maps.
arestore Restore image resolution using deconvolution techniques
asphist Bin the aspect solution into a 3D histogram of duration vs pointing offset and roll offset.
axbary Apply barycentric corrections to event times, GTIs, and header values.
calindex Create index file of calibration database (CALDB) products.
calquiz Find calibration files in the CALDB
calvalid Validate index file of calibration database (CALDB) products.
celldetect Use a "sliding cell" to search for sources
check_ciao_caldb A tool to test the installation of the CIAO Calibration Database (CALDB)
create_bkg_map Create a background map for ACIS and HRC from the event files.
csmooth Adaptively smooth a 2-D image
dax Run CIAO tasks from DS9's Analysis menu
deflare deflare - choose either the lc_clean() or lc_sigma_clip() routine from the lightcurves.py module to remove flares from light curves.
destreak Remove streak events from ACIS data
dither_region Compute fraction of region area that covers chips
dmappend Append multiple blocks/extensions to an existing output file.
dmarfadd Add multiple ARF files together, weighting by exposure.
dmcontour Make contour regions from a 2-D image
dmcoords Convert between Chandra coordinate systems
dmcopy Filter and bin tables and images.
dmdiff Compare values in two files.
dmellipse finds best fit ellipse for specified fraction
dmextract Make a histogram table file (e.g. PHA file, lightcurve file) from a table column. Generate count histogram on supplied regions for a spatial table or image file.
dmfilth Replace pixel values in source regions of an image with values interpolated from surrounding background regions
dmgroupreg Translates DS9 regions and groups to CIAO format.
dmgroup Group a specified column in a table with various options
dmgti Create a Good Time Interval from limits placed on time-based files (event and Mission Time Line files).
dmhedit Edit datamodel file headers
dmhistory Extracts the tool history from the file header
dmimg2jpg Make a color JPEG image (or EPS) from three image files
dmimgadapt Adaptively smoothes an image based on number of counts
dmimgblob Identifies groups of pixels above/below threshold
dmimgcalc Perform arithmetic on images
dmimgfilt Performs various non-linear image filtering techniques.
dmimghist Create a histogram of the pixel values in a 2-D image
dmimglasso Draw region around point with similar values
dmimgpick Maps image values to rows in a table
dmimgpm Compute a low frequency spatial (modified poisson mean) background map
dmimgproject Project image along axis
dmimgreproject Replicates table value along axis of image
dmimgthresh Set low (or high) intensity or exposure regions of an image to a constant value.
dmjoin Join two files whose sampling is different.
dmkeypar Retrieve information about a keyword from an input file
dmlist List contents or structure of a file.
dmmakepar Write header keywords to a parameter file
dmmakereg Convert a region string to a CXC FITS region file
dmmaskbin Bins an image based on input mask
dmmaskfill Replaces mask values with those found in lookup table
dmmath Syntax used for writing mathematical operations in dmtcalc, dmimgcalc, and dmgti
dmmerge Merge two or more compatible tables (e.g. event files) into one.
dmnautilus performs a quad-tree adaptive binning on 2D images
dmpaste Add new columns to a table.
dmreadpar Create header keywords from a parameter file
dmregrid2 shift, rotate, scale images
dmregrid Rebin a stack of 2-dimensional images.
dmsort Sort a table.
dmstat Compute statistics for images and columns in tables.
dmtcalc Modify and create columns in a table
dmtype2split Create a type 1 PHA output file for specified rows of a type 2 PHA file.
download_chandra_obsid Download public data by ObsId from the Chandra archive.
eff2evt Compute the flux and look up the QE & effective area for event positions
evalpos Get image values at a specified (RA,DEC)
fullgarf Create a grating ARF for a particular order and grating for a given observation.
get_sky_limits Find the region covered by an image in sky coordinates
get_src_region Outputs regions that have counts higher than background
glvary Search for variability using Gregory-Loredo algorithm.
hrc_bkgrnd_lookup Find the matching HRC "blank-sky" dataset (event file or spectrum) for an observation
hrc_build_badpix Create observation-specific bad pixel file for HRC
hrc_dtfstats Calculate statistics from hrc_calc_dead_time and a GTI
hrc_process_events Correct HRC event positions, times, PHA, etc.
lim_sens Create an output limiting sensitivity map with the same blocking factor, dimensions and WCS
make_instmap_weights make_instmap_weights - produces a weighted spectrum file usable with mkinstmap in order to create a weighted exposure map.
make_psf_asymmetry_region Create a region that shows the location of the HRMA PSF asymmetry for a source
merge_all Combine any number of observations. If desired, create corresponding exposure maps and exposure-corrected images.
mkacisrmf Generate an RMF for Chandra imaging data
mkarf Generate an ARF for Chandra imaging data (and grating 0-th order)
mkbgreg Creates a stack of background regions for a given source list
mkexpmap Generate a Chandra imaging exposure map (effective area vs. sky position)
mkgarf Generate a Chandra Grating ARF for one detector element.
mkgrmf Generate an RMF for Chandra grating data
mkinstmap Generate a Chandra instrument map (effective area vs. detector position)
mkpsfmap Look up the PSF-size for each pixel in an image
mkpsf Extract a point spread function (PSF) from the PSF library.
mkrmf Generate an RMF for Chandra imaging data
mksubbgreg Subtracts source regions from background regions
mkwarf Generate a weighted ARF for Chandra ACIS data
mtl_build_gti Create Good Time Interval from Mission Time Line and limits
paccess Gives the location of a tool's parameter file
pdump Dumps the values of the parameters, with one parameter per line.
pget Get parameter values
pileup_map Compute image that gives indication of pileup.
pline Display the parameter values, with all parameters on a single line
plist List the contents of a parameter file.
pquery Query whether a parameter exists and, if so, get and return its value.
pset Set parameter values on the command line
psextract Extract source and background ACIS spectra for point-like sources and build associated ARFs and RMFs.
psf_project_ray Project rays generated by ChaRT onto a semi-infinite detector plane.
punlearn Restore system default parameter values
reproject_aspect Modify aspect solution file RA, Dec, and roll or updfile WCS to minimize position differences between two source lists.
reproject_events Regrid an event file to a different tangent point
reproject_image_grid Projects image from one WCS to another
reproject_image Projects image from one WCS to another
rmfimg Create a simple image of an RMF or ARF file
skyfov Make a field-of-view region in sky coordinates
specextract Extract source and background ACIS spectra for point-like and extended sources and build associated WMAPs, ARFs and RMFs.
sso_freeze Reproject sky x and y coordinates into a Solar System Object centered reference frame.
stk_build stk_build is used to build a stack from a user-defined string. The output is to stdout, stderr, or a file.
stk_count stk_count is used to count the number of items in a stack. The output is to the stk_count parameter file.
stk_read_num stk_read_num is used to read one element of a user-defined stack. The output is to the outelement field of the stk_read_num parameter file.
stk_where stk_where finds the location of an item in a stack
tgdetect Detect and centroid the zero order image in a spatial sub-region of a grating event list.
tgextract2 Bin event list grating wavelengths column into a one-dimensional counts histogram, by source, grating part, and diffraction order. Optionally bin background spectrum.
tgextract Bin event list grating wavelengths column into a one-dimensional counts histogram, by source, grating part, and diffraction order.
tgidselectsrc Filter an input source list based upon a SNR threshold.
tgmatchsrc Match sources between two source lists by their 2-D separation files.
tg_bkg Creates a PHA background file for use in XSPEC
tg_create_mask Create a region file to define spectrum sky boundaries
tg_resolve_events Assign grating events to spectral orders; use detector energy resolution for order separation, if available.
vtpdetect Voronoi Tessellation and Percolation (VTP) source detection
wavdetect Mexican-Hat Wavelet source detection (wtransform+wrecon)
wcs_match Create a frame transformation to minimize the aspect difference between data from the same sky region.
wcs_update Modify aspect solution file RA, Dec, and roll or infile WCS based on a transformation matrix.
wrecon Combine wavelet transform coefficients into sources
wtransform Obtain wavelet transform coefficients for poisson image data

Last modified: 26 October 2010