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Last modified: 23 March 2007
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Contextual list of Ahelp files for CIAO 3.4

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ahelp caldb calibration chandra chips concept dm ds9 group gui guide modules paramio pixlib proposaltools region sherpa slang slangrtl stackio tools varmm varmmrl xpa

Context Topic Summary
ahelp ahelp Access the CIAO help documentation.

caldb calCreateInfo Create a CALDB structure for use in other CALDB calls.
calFindFile Query the Calibration Database for a file
calGetData Returns the code name stored in the CALDB structure.
calGetDate Returns the observation start date stored in the CALDB structure.
calGetDetector Returns the name of the detector stored in the CALDB structure.
calGetError Returns the severity of the last CALDB error.
calGetFilter Returns the name of the filter stored in the CALDB structure.
calGetInstrument Returns the name of the instrument stored in the CALDB structure.
calGetQuery Returns the value of the query expression stored in the CALDB structure.
calGetTelescope Returns the name of the telescope stored in the CALDB structure.
calGetTime Returns the observation start time stored in the CALDB structure.
calPrintInfo Display the contents of the CALDB structure
calSetData Sets the data product code name for the next CALDB query.
calSetDate Sets the date for the next CALDB query.
calSetDetector Sets the name of the detector in the CALDB structure.
calSetExpression Sets the boundary condition(s) for the CALDB query.
calSetFilter Sets the filter to be used in a CALDB query.
calSetInstrument Sets the name of the instrument in the CALDB structure.
calSetTelescope Sets the name of the telescope in the CALDB structure.
calSetTime Sets the time for the next CALDB query.

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
guide Grating User Interactive Data Extension (GUIDE)
isis Interactive Spectral Interpretation System (ISIS)
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

chips axes Specifies the appearance of the bounding box surrounding a drawing area. The command AXIS is equivalent.
batch Turns on/off use of a plotting device.
browse Launches the CIAO file-browsing GUI, Prism. The command PRISM is equivalent.
chips_auto_redraw Set the automatic redrawing mode.
chips_clear Removes all plotting objects, creating a new blank drawing area.
chips_color_name Converts a color number to a string.
chips_color_value Converts the name of a color to its numeric value.
chips_eval Call ChIPS commands from S-Lang
chips_get_pane Get the current pane/drawing area.
chips_get_xrange Get the upper and/or lower x-axis limits of the plot
chips_get_xscale Get the x-axis scale
chips_get_yrange Get the upper and/or lower y-axis limits of the plot
chips_get_yscale Get the y-axis scale
chips_get_zrange Get the upper and/or lower z-axis limits of the plot
chips_get_zscale Get the z-axis scale
chips_label Adds a label to a drawing area.
chips_line Adds a line to a drawing area.
chips_pickpoints Read 1 or more cursor positions from ChIPS.
chips_redraw Redraws all plotting objects.
chips_set_pane Set the current pane/drawing area.
chips_set_xrange Set the upper and/or lower x-axis limits of the plot
chips_set_xscale Set the x-axis scale
chips_set_yrange Set the upper and/or lower y-axis limits of the plot
chips_set_yscale Set the y-axis scale
chips_set_zrange Set the upper and/or lower z-axis limits of the plot
chips_set_zscale Set the z-axis scale
chips_split Creates multiple drawing areas.
chips_version Report the version of ChIPS as a number or string.
chips Introduction to ChIPS, CIAO's plotting package.
clear Removes all plotting objects and creates a new blank drawing area.
colorsys Sets the color system for hardcopy plots.
contour Adds a contour plot to a drawing area.
curve Plots a curve or change its attributes (PLOT is equivalent).
c Defines the current curve.
delete Deletes plotting objects (drawing area, curves, lines and labels) from a plot.
display Causes the specified 2-D data to be displayed, using the default imaging display tool (i.e. ds9)
drawarea Specifies the location for a new drawing area.
d Defines the current drawing area.
errs Specifies the appearance of errorbars.
exit Terminates the program. The command QUIT is equivalent.
font Changes the default global font.
grids Adds grid lines to a drawing area and/or changes grid attributes.
info Prints summary information about the current plotting objects.
label Adds a label to a drawing area and/or changes label attributes.
levels Sets the contour levels in a contour plot.
limits Sets the ranges to be displayed in the axes.
linear Changes one or more axes to linear scale.
line Adds a line to a drawing area and/or changes line attributes.
list Lists the contents of datafiles using the CIAO tool dmlist.
ln Defines the current line.
location Specifies the location for an existing drawing area.
log Changes one or more axes to logarithmic scale.
l Defines the current label.
pack Renumbers plotting objects after a delete operation.
pagesize Sets the page dimensions for hardcopy plots.
pickpoints Starts the interactive cursor mode, which reads out the cursor position.
print Creates a hardcopy of the current plot.
redo Redoes the most recently undone plotting command.
redraw Redraws the plot or sets the redraw mode
relativesize Alters the relative size of drawing areas. The command RELSIZE is equivalent.
restore Restores a plot with all attributes.
skip Skips the designated number of lines from subsequent input files.
split Creates multiple drawing areas and/or arranges their locations.
store Saves a plot with all attributes.
surface Adds a surface plot to a drawing area.
symbol Specifies the appearance of symbols in a curve.
ticks Specifies the spacing of tick marks.
tickvals Controls the appearance of numerical tick mark labels.
title Adds a title and/or changes the title attribute.
type Reports the data that are associated with a curve.
undo Undoes the most recently executed plotting command.
verbose Regulates reporting of error and informational messages.
viewpoint Controls the rotation angle of a surface plot.
xlabel Adds a label along the X-axis of a drawing area and/or changes X-axis label attributes.
ylabel Adds a label along the Y-axis of a drawing area and/or changes Y-axis label attributes.
zlabel Adds a label along the Z-axis of a drawing area and/or changes Z-axis label attributes.

concept autoname Autonaming is a feature available in various tools for automatically naming an output file based upon the name of an input file.
ciao Chandra Interactive Analysis of Observations
configure Configuration and customization of CIAO
merging_rules A description of the merging rules used when combining header information.
parameter Describes the parameter interface used by CIAO.
session A session is a conceptual notion of how various CIAO applications interact with each other to form an integrated data analysis environment.
stack How to set a parameter to more than one value using a stack.
subspace Describes the filtering applied to a file

dm dmbinning The CIAO binning syntax
dmcols Selecting columns in a table
dmfiltering The CIAO filtering syntax
dmimages Images in CIAO: logical and physical coordinate systems
dmimfiltering The CIAO filtering syntax for images
dmintro The Data Model library underlies most of the CXC tools.
dmopt Controlling data model internal options
dmregions CIAO region filtering syntax
dmsyntax The Data Model syntax for filtering and binning files.
dm The CIAO Data Model

ds9 ds9_center Center image at position
ds9_clear Erase a DS9 frame
ds9_get_array Retrieve displayed image
ds9_get_cmap Retrieve colormap from DS9
ds9_get_coords Retrieve position of next mouseclick within any frame
ds9_get_crosshair Retrieve position of crosshair cursor
ds9_get_file Retrieve name of file being displayed
ds9_get_regions Retrieve descriptions of regions applied to a displayed image
ds9_get_scale Retrieve image scale
ds9_get_zoom Retrieve zoom level
ds9_launch Establish connection to a DS9 process
ds9_pan Shift image position
ds9_put_array Visualize an image pixel array
ds9_put_crosshair Set position of crosshair cursor
ds9_put_file Load FITS file
ds9_put_regions Request that region descriptions be applied to the displayed image
ds9_put_wcs_keys Apply WCS to displayed image, using pre-formatted FITS keywords
ds9_put_wcs_struct Apply WCS to displayed image, using structure field values
ds9_put_wcs Apply WCS to displayed image, using raw numeric or string values
ds9_quit Terminate a DS9 process
ds9_set_cmap Change colormap of DS9
ds9_set_scale Change image scale
ds9_set_zoom Zoom in or out
ds9_view Launch DS9 with file or image pixel array

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 The "Analysis" menu in CIAO GUIs allows users to run command-line tools.
ciao.par Parameter file to configure options for CIAO applications.
ciaoshmem Provides information on and configuration of CIAO sessions.
filtwin GUI to perform interactive filtering of data
firstlook GUI to allow an efficient means of accessing Chandra data products
gui Graphical User Interface (GUI)
peg 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

guide describe Describe is a GUIDE command that prints out detailed information about either one or two energy levels and, if two levels are input, any atomic transitions between them.
identify List emission lines near given wavelength.
ionbal Calculate collisional ionization equilibrium ion balance.
mdl2latex Output latex table of fitted emission lines and fluxes.
strong List "strong" emission lines at a given temperature, within specified wavelength bounds.

modules caldb The S-Lang interface to the CXC CALDB library
ds9 A simple S-Lang interface to ds9
group 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
varmmrl The Varmm readline module for S-Lang
varmm The Variable, Math and Macro S-Lang library
xpa The S-Lang interface to the XPA 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_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 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 Observation Visualizer
pimms PIMMS (Portable, Interactive Multi-Mission Simulator) converts source fluxes and count rates between missions.
precess Interactive astronomical coordinate conversion program that 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 Chandra Proposal Tools
prop-tools Tools that aid in the preparation and submission of Chandra proposals

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.

sherpa analysis Specifies whether to analyze datasets in energy, wavelength, or channel space.
atten Attenuation by ISM. Integration OFF.
autoest Automatic estimation of initial parameter values in Sherpa models
background Defines a model expression to be used for the background. The command BG is an abbreviated equivalent.
back Inputs the contents of one or more background data files.
bayes A Bayesian maximum likelihood function.
bbodyfreq Blackbody as a function of frequency. Integration ON.
bbody Blackbody as a function of energy. Integration ON.
berrors Defines an expression to be used to specify the statistical errors for background data. The commands BACKERRORS and BSTATERRORS are equivalent.
beta1d 1-D surface brightness beta-model. Integration OFF
beta2d 2-D Lorentzian with varying power law. Integration OFF. The LORPOW2D model is equivalent.
box1d 1-D box function. Integration OFF.
box2d 2-D box function. Integration OFF.
bpl1d Broken power law function. Integration ON.
bsyserrors Defines an expression or file to be used to specify the systematic errors for background data.
bye Terminates the Sherpa program. Other equivalent termination commands are EXIT and QUIT.
calc_kcorr Calculate the k correction for a spectral model, redshift, and energy range.
cash A maximum likelihood function.
cast [REMOVED AS OF CIAO 3.0.2] Casts a dataset to single or double precision.
chicvar Chi-square statistic with constant variance computed from the counts data.
chidvar Chi-square statistic with variance computed from the data.
chigehrels Chi-square statistic with the Gehrels variance function.
chimvar Chi-square statistic with variance computed from model amplitudes.
chiprimini Chi-square statistic with Primini variance function.
chisquare Chi-square statistic.
close Closes the image display window.
compute_errors Module function to estimate errors for an array of data
compute_statistic Module function to estimate a statistic given arrays of data, model amplitudes, and errors, etc.
const1d 1-D constant amplitude model. Integration ON.
const2d 2-D constant amplitude model. Integration ON.
coord Specifies the coordinate system for use in fits to 2-D images.
cos Cosine function. Integration OFF.
covariance Computes covariance matrices, and provides an estimate of confidence intervals for selected thawed parameters.
cplot Causes the specified 2-D data to be displayed, with a contour plot, via ChIPS.
createparamset To be especially efficient, one may establish and assign a name to a model component, as well as set model parameters and their ranges, all at one time using a single command:
create_model Module functions to instantiate new source or instrument models.
create Establishes a model component and its parameters, for use in the current Sherpa session.
cstat A maximum likelihood function.
dataspace Creates a data grid on which models may be evaluated.
data Inputs the contents of one or more source data files.
dcounts Calculates the sum of observed counts data for source or background datasets.
delta1d 1-D delta function. Integration ON.
delta2d 2-D delta function. Integration ON.
dered Dereddening function. Integration OFF.
devaucouleurs DeVaucouleurs profile. Integration OFF.
dollarsign Must precede any Unix command issued within Sherpa or ChIPS.
echo Turns on/off reporting of user keystrokes.
edge Photoabsorption edge model. Integration OFF.
eflux Calculates the unconvolved energy flux for source or background datasets.
eqwidth Computes the equivalent width of an emission or absorption line in source or background data.
erase Erases user inputs and settings, and/or model components.
erfc A 1-D complementary error function. Integration OFF.
erf A 1-D error function. Integration OFF.
errors Defines an expression to be used to specify the statistical errors for source data.
fakeit Creates a simulated 1-D dataset.
farf2d A 2-D file-based ancillary response model. Alternate names include FEXPMAP and FEXPMAP2D.
farf A 1-D file-based ancillary response model.
feffile Specifies the Fits Embedded Function (FEF) file whose contents will be displayed with FEFPLOT.
fefplot Plots an instrument response stored in a Fits Embedded Function (FEF) file that is read in via FEFFILE.
fit Initiates fitting (optimization). The command [B]RUN is equivalent.
flux Calculates the unconvolved photon flux for source or background datasets.
fpsf1d A 1-D file-based PSF instrument model.
fpsf A 2-D file-based PSF instrument model.
freeze Prohibits model parameter(s) from varying.
frmf A 1-D file-based response matrix model.
ftest Computes significance using the F test.
gauss1d 1-D unnormalized Gaussian function. Integration ON.
gauss2d 2-D unnormalized Gaussian function. Integration OFF.
getx Assigns x-axis values taken from a plot to model parameters.
gety Assigns y-axis values taken from a plot to model parameters.
get_analysis Module function to retrieve the current analysis setting.
get_arf_axes Module functions to retrieve the energy/wavelength grid of an ARF associated with source and background data
get_axes Module functions to get the energy/wavelength/channel grid of source and background datasets.
get_coord Module function to retrieve the current coordinate setting for 2-D image data.
get_data Module functions to get the amplitudes of source and background datasets.
get_dcounts_sum Calculates the sum of observed counts in source and background datasets using module functions in Sherpa.
get_defined_models Module functions that return lists of defined Sherpa source and instrument models
get_dir Module function to retrieve the current path.
get_eflux Calculate the energy flux (unconvolved) for source or background datasets using module functions in Sherpa.
get_energy_axes Module functions to retrieve the energy grids of source and background datasets.
get_eqwidth Module functions that compute the equivalent width of an emission or absorption line in source or background data.
get_errors Module functions to get the error estimates of source and background datasets.
get_filename Module functions to retrieve filenames associated with a dataset.
get_filter_expr Module function to retrieve the strings describing filters applied to source and background datasets.
get_filter Module functions to get the filter arrays associated with source and background datasets.
get_fit Module functions to get information about the quality of a fit.
get_flux2d Module functions for computing fluxes/summing counts in 2-D images.
get_fluxed_spectrum Retrieve a fluxed spectrum (counts divided by ARF) using module functions in Sherpa.
get_flux_str Retrieves a default structure for use with get_pflux(), etc.
get_ftest Module function that returns the statistical significance computed with the F test
get_groups Module functions for retrieving a grouping or quality array from source and background files.
get_lfactorial Module function to compute the natural logarithm of the factorial of the input quantity
get_mcounts_sum Module functions for computing the sum of convolved model counts in source and background datasets.
get_metadata Module functions to retrieve metadata associated with source and background datasets.
get_method_expr Module function to retrieve the name of the current optimization method.
get_models Module functions that return lists of available source and instrument models
get_model_params Access to the default model and instrument parameters of Sherpa from S-Lang.
get_num_par Module functions that report the total number of parameters for all defined models, including instrument models
get_paramestint Module functions to retrieve the value and statistic arrays from the most recent run of a parameter estimation method
get_paramestlim Module functions to determine confidence intervals, and retrieve the parameter bounds.
get_paramestreg Module functions to retrieve the value and statistic arrays from the most recent run of a parameter estimation method
get_paramest Module functions to retrieve the output of parameter estimation methods.
get_par Module function for getting model parameter values, etc.
get_pflux get_flux(), get_pflux(), and get_bpflux() calculate the photon flux (unconvolved) for source and background datasets using the module functions in Sherpa.
get_photon_axes Module functions to retrieve photon-space grids over which models are evaluated.
get_photon_energy_axes Module functions to retrieve photon-space energy grids over which models are evaluated.
get_photon_wave_axes Module functions to retrieve photon-space wavelength grids over which models are evaluated.
get_qvalue Module function that returns the statistical significance computed as a q-value.
get_raw_axes Module functions to retrieve the raw channel number grids of source and background datasets.
get_record Module function to return a record of model parameter values at the end of each iteration of the fitting process.
get_source_components Return, as an array, the names of the model components in the source expression of a dataset.
get_source Module functions to retrieve predicted source and background model photon amplitudes.
get_stackexpr Module functions to retrieve a model stack expression.
get_statistic Module functions to get the current value of the statistic comparing source and background data and model values.
get_stats Module functions to retrieve predicted model counts, statistics, residuals, sigma residuals, and ratios from source and background datasets.
get_stat_expr Module function to retrieve the name of the current statistic.
get_syserrors Module functions to get the systematic error estimates of source and background datasets.
get_verbose Module function to display Sherpa's current verbosity setting.
get_wave_axes Module functions to retrieve the wavelength grids of source and background datasets.
get_weights Module functions to get the statistical weights of source and background datasets.
get Summary of Sherpa/S-Lang module functions that retrieve settings or data.
goodness Reports information on the goodness-of-fit.
grid-powell A grid search utilizing the Powell method at each grid point.
gridmodel N-D user-specified amplitude model. Integration OFF.
grid A grid search of parameter space, with no minimization.
groupByCounts Group a dataset by number of counts or signal-to-noise within Sherpa.
group Causes Sherpa to apply a read-in bin grouping scheme to source or background data.
guess Estimates initial parameter values and ranges, based on input data.
hubble Hubble-Reynolds profile. Integration OFF. The REYNOLDS model is equivalent.
ignore Specifies a data portion to be excluded, for 1- or 2-D data.
image Causes the specified 2-D data to be displayed, via ds9.
instrument Defines an expression to be used for modeling the instrument in source or background data analysis. The command RESPONSE is equivalent.
integrate Controls the integration of model components.
interval-projection Plots the fit statistic as a function of parameter value, using the PROJECTION algorithm. The commands INT-PROJ and INTPROJ are abbreviated equivalents.
interval-uncertainty Plots the fit statistic as a function of parameter value, using the UNCERTAINTY algorithm. The commands INT-UNC and INTUNC are abbreviated equivalents.
is_paramset Module functions to determine if whether the specified parameter(s) are thawed or frozen.
is_subtracted Module function to determine if whether the specified dataset is background-subtracted.
is Summary of Sherpa/S-Lang module query functions.
jdpileup A CCD pileup model developed by John Davis of MIT.
jointmode Joint-mode models define the function argument, on which a model expression is evaluated, to be a particular data axis.
journal Turns on/off the writing of all commands to a file.
kernel Defines an expression to be used as a kernel in 1D source model convolution.
levenberg-marquardt The Levenberg-Marquardt optimization method.
linebroad Line broadening profile. Integration ON.
lineid Sets a user-defined line identification (or general model description) for the model in the MDL output.
linkparam Parameter expressions are used to link model component parameters:
list_paramest Module functions listing the current and default values of the parameters used to configure each Sherpa parameter estimation method.
list_par Module function that lists information about all defined model parameters.
list Summary of Sherpa/S-Lang module list functions.
load_arf Module function to load data from an ARF file into Sherpa
load_ascii Module function to load ASCII data into Sherpa
load_backset Module function to load background data into Sherpa
load_back_from Module function to load background from a PHA file into Sherpa
load_dataset Module function to load data into Sherpa
load_fitsbin Module functions to load source and background data from a FITS binary table into Sherpa
load_image Module functions to load source and background data from a FITS image into Sherpa
load_inst_from Module function to load data from ARF and RMF files into Sherpa source or background instrument models.
load_inst Module function to load data from ARF and RMF files into Sherpa. load_instrument is an alternate name.
load_pha2 Module function to load source data from PHA Type II files into Sherpa
load_pha Module function to load source and background data from PHA Type I files into Sherpa
load_rmf Module function to load data from an RMF file into Sherpa
load Summary of Sherpa/S-Lang module functions that load data into Sherpa
lorentz1d 1-D normalized Lorentzian function. Integration ON.
lorentz2d 2-D unnormalized Lorentzian function. Integration OFF.
lplot Causes the specified 1-D data to be displayed, via ChIPS.
mcounts Calculates the sum of convolved model amplitudes for source or background datasets.
mdl A Model Descriptor List (MDL) file stores a collection of datasets and model(s) in a structured format that can be read or written by Sherpa.
method Specifies the optimization method. The command SEARCHMETHOD is equivalent.
mlr Computes significance using the Maximum Likelihood Ratio test.
modelexpr Model components can be used to create model expressions, in conjunction with the SOURCE and BACKGROUND commands (which then are used to fit the data), or with model stacks:
modelstack A model stack assigns an arbitrary name to a model expression, for subsequent use in parameter expressions and/or nested models.
models Summary of Available Models
monte-lm A Monte Carlo search utilizing the Powell method at each selected point.
monte-powell A Monte Carlo search utilizing the Powell method at each selected point.
montecarlo A Monte Carlo search of parameter space.
nbeta 1-D normalized beta function. Integration ON.
nestedmodel Nested models define the function argument on which a model expression is evaluated to be another model expression. A nested model, <nested_model>, appears as an element of a model expression, <modelExpr>.
ngauss1d 1-D normalized Gaussian function. Integration ON.
noise Defines an expression to be used for modeling detector noise in source and background datasets.
notice Specifies a data portion to be included, for 1- or 2-D data.
numbersign Denotes a comment. The symbol % also denotes a comment.
open Opens the image display window.
oplot Causes multiple data curves to be displayed in the same drawing area, via ChIPS.
paramest An interactive interface to the parameter estimation routines in Sherpa.
paramprompt Turns on/off prompting for model parameter values.
paramset The model components that have been established in the current Sherpa session, and their parameter information, may be listed with the command SHOW MODELS. Values for these established model component parameters may be set individually using one of the following command syntax options:
pileup Defines the pileup model expression to be used for fitting a 1D dataset.
plotx [REMOVED AS OF CIAO 3.0.2] Sets the unit type for the x-axis of a plot.
ploty Sets the unit type for the y-axis of a plot.
plot_eprof Display a radial profile (elliptical annuli) of 2D data, fit, and residuals.
plot_rprof Display a radial profile (circular annuli) of 2D data, fit, and residuals.
poisson Poisson function. Integration OFF.
polynom1d 1-D polynomial function. Integration ON.
polynom2d 2-D polynomial function. Integration ON.
powell The Powell optimization method.
powlaw1d 1-D power law. Integration ON.
projection Estimates confidence intervals for selected thawed parameters.
prompt Changes the Sherpa prompt.
ptsrc1d A 1-D file-based point-source fitting model.
ptsrc2d A 2-D file-based point-source fitting model.
read Inputs the contents of one or more files.
record Controls output of parameters values and statistics to an ASCII file.
region-projection Creates a contour plot of confidence regions using the PROJECTION algorithm. The commands REG-PROJ and REGPROJ are abbreviated equivalents.
region-uncertainty Creates a contour plot of confidence regions using the UNCERTAINTY algorithm. The commands REG-UNC and REGUNC are abbreviated equivalents.
rename Changes the name that has been given to a model component by the user.
reset Restores settings and/or parameter values.
restore_paramest Module functions to restore the default values of the parameters used to configure each Sherpa parameter estimation method.
rsp2d A 2-D instrument model utilizing an exposure map and point-spread function.
rsp A 1-D instrument model.
run_fit Module function to fit datasets, and retrieve information about the final fit.
run_paramestint Module functions to display statistics as a function of parameter value, and to retrieve the value and statistic arrays
run_paramestlim Module functions to determine confidence intervals, and retrieve the parameter bounds.
run_paramestreg Module functions to display contours of statistics as a function of parameter values, and to retrieve arrays of values and statistics
run_paramest Module functions to run parameter estimation routines and retrieve information.
run Summary of Sherpa/S-Lang module run functions.
save_state The save_state() function
save Saves information to an ASCII file.
schechter Schechter function. Integration OFF.
setback Sets attributes of a background dataset.
setdata Sets attributes of a source dataset.
setplot An alternative interface to the Sherpa plot customisation variables
set_analysis Module function to set the units for 1-D spectral analysis.
set_axes Module functions for creating new source or background dataspaces.
set_backscale Module functions for setting source and background extraction region areas.
set_coord Module function to set the coordinate system for 2-D image analysis.
set_dataspace An alternative form of DATASPACE and set_axes().
set_data Set source and background data using the S-lang module function in Sherpa.
set_dir Module function to change directories.
set_erroff Switch off the drawing of error bars in Sherpa plots
set_erron Switch on the drawing of error bars in Sherpa plots
set_errors Module functions for assigning source and background error estimates.
set_exptime Module functions for setting source and background exposure times.
set_filter Module functions for assigning source and background filters from an array.
set_groups Module functions for grouping and setting quality to source and background files from an array.
set_ignore2d Module functions for ignoring source and background regions in 2-D datasets.
set_ignore_all Module functions for ignoring all source and background data.
set_ignore_bad Module functions for ignoring bad (quality > 0) channels.
set_ignore Module functions for ignoring source and background filter ranges in 1-D datasets.
set_lin Switch plotting axis to linear scale in Sherpa plots
set_log Switch axis to log in Sherpa plots
set_notice2d Module functions for noticing source and background regions in 2-D datasets.
set_notice_all Module functions for noticing all source and background data.
set_notice Module functions for noticing source and background filter ranges in 1-D datasets.
set_paramset Module functions to thaw or freeze the specified parameter(s).
set_par Module function for setting model parameter values, etc.
set_stackexpr Module functions to set a model stack expression.
set_subtract Module functions to subtract background from a source dataset, or to undo subtraction.
set_syserrors Module functions for assigning source and background systematic error estimates.
set_verbose Module function to reset Sherpa's verbosity.
set_weights Module functions for assigning source and background statistical weights.
set Summary of Sherpa/S-Lang module functions that change settings or data.
sherpa-module Accessing data with the Sherpa/S-Lang module functions.
sherpa-plot-hooks Customizing Sherpa plots using the prefunc and postfunc fields of Sherpa State Objects
sherpa.cov Configure COVARIANCE in Sherpa.
sherpa.dataplot Configure appearance of Sherpa plots.
sherpa.fitplot Configure appearance of Sherpa plots.
sherpa.intproj Configure INTERVAL-PROJECTION in Sherpa.
sherpa.intunc Configure INTERVAL-UNCERTAINTY in Sherpa.
sherpa.multiplot Configure appearance of Sherpa plots.
sherpa.output A Description of the sherpa.output State Object
sherpa.plot Configure appearance of Sherpa plots.
sherpa.proj Configure PROJECTION in Sherpa.
sherpa.regproj Configure REGION-PROJECTION in Sherpa.
sherpa.regunc Configure REGION-UNCERTAINTY in Sherpa.
sherpa.resplot Configure appearance of Sherpa plots.
sherpa.unc Configure UNCERTAINTY in Sherpa.
sherpa_eval Call Sherpa commands from S-Lang
sherpa_plotfns Plot-related functions for Sherpa.
sherpa_utils Provides a number of S-Lang functions useful for Sherpa.
sherpa Command summary of Sherpa, CIAO's modeling and fitting engine.
shexp10 Exponential function, base 10. Integration OFF.
shexp Exponential function. Integration OFF.
shlog10 Logarithm function, base 10. Integration OFF.
shloge Natural logarithm function. Integration OFF.
show Reports current status.
sigma-rejection The SIGMA-REJECTION optimization method for fits to 1-D data. Alternate names are SIG-REJ and SR.
simplex A simplex optimization method.
simspec Create and fit a simulated PHA spectrum.
simul-ann-1 A simulated annealing search, with one parameter varied at each step.
simul-ann-2 A simulated annealing search, with all parameters varied at each step.
simul-pow-1 A combination of SIMUL-ANN-1 with POWELL.
simul-pow-2 A combination of SIMUL-ANN-2 with POWELL.
sin Sine function. Integration OFF.
source Defines the source model expression to be used for fitting a dataset. The command SRC is an abbreviated equivalent.
splot Causes the specified 2-D data to be displayed, with a surface plot, via ChIPS.
sqrt Square root function. Integration OFF.
staterrors Defines an expression or file to be used to specify the statistical errors for source data.
statistic Specifies the fitting statistic.
stephi1d 1-D step function. Integration OFF. The command HIGHPASS is equivalent.
steplo1d 1-D step function. Integration OFF. The command LOWPASS is equivalent.
subtract Performs background subtraction.
syserrors Defines an expression or file to be used to specify the systematic errors for source data.
tan Tangent function. Integration OFF.
thaw Allows model parameter(s) to vary.
tpsf1d A 1-D TCD-model-based instrument model.
tpsf A 2-D TCD-model-based instrument model.
truncate Resets negative model amplitudes to zero.
uncertainty Estimates confidence intervals for selected thawed parameters.
ungroup Causes Sherpa to undo a grouping scheme that had been applied to source or background data.
unlink Removes a link between model parameters.
unsubtract Undoes background subtraction.
usermethod A user-defined method.
usermodel User implemented model. Integration OFF.
userstat User implemented statistic.
use Calls and executes a Sherpa script.
version Reports the Sherpa version that is in use.
write Causes the specified information to be written to the screen or to a file.
xsabsori Ionized absorber. XSpec model.
xsacisabs Decay in the ACIS quantum efficiency. XSpec model.
xsapec APEC thermal plasma model. XSpec model.
xsbapec APEC thermal plasma model with velocity broadening as a free parameter. XSpec model.
xsbbodyrad Blackbody spectrum with norm proportional to surface area. XSpec model.
xsbbody Blackbody spectrum. XSpec model.
xsbexrav E-folded broken power law reflected from neutral matter. XSpec model.
xsbexriv E-folded broken power law reflected from ionized matter. XSpec model.
xsbknpower Broken power law. XSpec model.
xsbmc Comptonization by relativistically moving matter. XSpec model.
xsbremss Thermal bremsstrahlung. XSpec model.
xsbvapec APEC thermal plasma model with variable abundances and velocity broadening as a free parameter. XSpec model.
xsc6mekl 6th-order Chebyshev polynomial DEM using mekal. XSpec model.
xsc6pmekl Exponential of 6th-order Chebyshev polyn. DEM using mekal. XSpec model.
xsc6pvmkl Variable abundance version of c6pmekl. XSpec model.
xsc6vmekl Variable abundance version of c6mekl. XSpec model.
xscabs Compton scattering (non-relativistic). XSpec model.
xscemekl Multi-temperature mekal. XSpec model.
xscevmkl Multi-temperature vmeka. XSpec model.
xscflow Cooling flow model. XSpec model.
xscompbb Comptonized blackbody spectrum after Nishimura et al. (1986). XSpec model.
xscompls Comptonization spectrum after Lamb and Sanford (1979). XSpec model.
xscompst Comptonization spectrum after Sunyaev and Titarchuk (1980). XSpec model.
xscomptt Comptonization spectrum after Titarchuk (1994). XSpec model.
xsconstant Energy-independent multiplicative factor. XSpec model.
xscutoffpl Power law with high energy exponential cutoff. XSpec model.
xscyclabs Cyclotron absorption line. XSpec model.
xsdiskbb Multiple blackbody disk model. XSpec model.
xsdiskline Line emission from relativistic accretion disk. XSpec model.
xsdiskm Disk model with gas pressure viscosity. XSpec model.
xsdisko Modified blackbody disk model. XSpec model.
xsdiskpn Accretion disk around a black hole. XSpec model.
xsdisk Disk model. XSpec model.
xsdust Dust scattering out of the beam. XSpec model.
xsedge Absorption edge. XSpec model.
xsequil Equilibrium ionization collisional plasma model from Borkowski. XSpec model.
xsexpabs Low-energy exponential cutoff. XSpec model.
xsexpdec An exponential decay. XSpec model.
xsexpfac Exponential factor. XSpec model.
xsgabs A multiplicative gaussian absorption line. XSpec model.
xsgaussian Simple gaussian line profile. XSpec model.
xsgnei Generalized single ionization NEI plasma model. XSpec model.
xsgrad GR accretion disk around a black hole. XSpec model.
xsgrbm Gamma-ray burst model. XSpec model.
xshighecut High energy cutoff. XSpec model.
xshrefl Simple reflection model good up to 15 keV. XSpec model.
xslaor Line from accretion disk around a black hole. XSpec model.
xslorentz Lorentzian line profile. XSpec model.
xsmekal Mewe-Kaastra-Liedahl thermal plasma (1995). XSpec model.
xsmeka Mewe-Gronenschild-Kaastra thermal plasma (1992). XSpec model.
xsmkcflow Cooling flow model based on mekal. XSpec model.
xsnei Simple nonequilibrium ionization plasma model. XSpec model.
xsnotch Notch line absorption. XSpec model.
xsnpshock Plane-parallel shock with ion and electron temperatures. XSpec model.
xsnsa Spectra in the X-ray range (0.05-10 keV) emitted from a hydrogen atmosphere of a neutron star. XSpec model.
xsnteea Pair plasma model. XSpec model.
xspcfabs Partial covering fraction absorption. XSpec model.
xspecabundan Performs the XSPEC command abund.
xspecxsect Performs the XSPEC command xsect.
xspegpwrlw Power law with pegged normalization. XSpec model.
xspexrav Exponentially cutoff power law reflected from neutral matter. XSpec model.
xspexriv Exponentially cutoff power law reflected from ionized matter. XSpec model.
xsphabs Photo-electric absorption. XSpec model.
xsplabs Absorption model with power law dependence on energy. XSpec model.
xsplcabs Cutoff power law observed through dense, cold matter. XSpec model.
xsposm Positronium continuum. XSpec model.
xspowerlaw Simple photon power law. XSpec model.
xspshock Constant temperature, plane-parallel shock plasma model. XSpec model.
xspwab An extension of partial covering fraction absorption into a power-law distribution of covering fraction. XSpec model.
xsraymond Raymond-Smith thermal plasma. XSpec model.
xsredden IR/optical/UV extinction from Cardelli et al. (1989). XSpec model.
xsredge Recombination edge. XSpec model.
xsrefsch E-folded power law reflected from an ionized relativistic disk. XSpec model.
xssedov Sedov model with electron and ion temperatures. XSpec model.
xssmedge Smoothed absorption edge. XSpec model.
xsspline Spline multiplicative factor. XSpec model.
xssrcut Synchrotron radiation from cutoff electron distribution. XSpec model.
xssresc Synchrotron radiation from escape-limited electron distribution. XSpec model.
xssssice Einstein Observatory SSS ice absorption. XSpec model.
xsstep Step function convolved with gaussian. XSpec model.
xstbabs Calculates the absorption of X-rays by the ISM. XSpec model.
xstbgrain Calculates the absorption of X-rays by the ISM with variable hydrogen to H2 ratio and grain parameters. XSpec model.
xstbvarabs Calculates the absorption of X-rays by the ISM, allowing user to vary all abundances, depletion factors, and grain properties. XSpec model.
xsuvred UV reddening. XSpec model.
xsvapec APEC thermal plasma model with variable abundances. XSpec model.
xsvarabs Photoelectric absorption with variable abundances. XSpec model.
xsvbremss Thermal bremsstrahlung spectrum with variable H/He. XSpec model.
xsvequil Ionization equilibrium collisional plasma model with variable abundances. XSpec model.
xsvgnei Non-equilibrium ionization collisional plasma model with variable abundances. XSpec model.
xsvmcflow Cooling flow model based on vmekal. XSpec model.
xsvmekal M-K-L thermal plasma with variable abundances. XSpec model.
xsvmeka M-G-K thermal plasma with variable abundances. XSpec model.
xsvnei Non-equilibrium ionization collisional plasma model with variable abundances. XSpec model.
xsvnpshock Plane-parallel shock plasma model with separate ion and electron temperatures and variable abundances. XSpec model.
xsvphabs Photoelectric absorption with variable abundances. XSpec model.
xsvpshock Constant temperature, plane-parallel shock plasma model with variable abundances. XSpec model.
xsvraymond Raymond-Smith thermal plasma with variable abundances. XSpec model.
xsvsedov Sedov model with separate ion and electron temperatures and variable abundances. XSpec model.
xswabs Photoelectric absorption (Morrison and McCammon). XSpec model.
xswndabs Photoelectric absorption with low energy window. XSpec model.
xsxion Reflected spectra of a photo-ionized accretion disk or ring. XSpec model.
xszbbody Redshifted blackbody. XSpec model.
xszbremss Redshifted thermal bremsstrahlung. XSpec model.
xszedge Redshifted absorption edge. XSpec model.
xszgauss Redshifted gaussian. XSpec model.
xszhighect Redshifted high energy cutoff. XSpec model.
xszpcfabs Redshifted partial covering absorption. XSpec model.
xszphabs Redshifted photoelectric absorption. XSpec model.
xszpowerlw Redshifted power law. XSpec model.
xsztbabs Calculates the absorption of X-rays by the ISM for modeling redshifted absorption. Does not include a dust component. XSpec model.
xszvarabs Redshifted photoelectric absorption with variable abundances. XSpec model.
xszvfeabs Redshifted absorption with variable iron abundance. XSpec model.
xszvphabs Redshifted photoelectric absorption with variable abundances. XSpec model.
xszwabs Redshifted "Wisconsin absorption." XSpec model.
xszwndabs Redshifted photoelectric absorption with low energy window. XSpec model.
xs XSpec model functions.

slang math Mathematical operations in S-Lang.
overview Overview of the S-Lang programing language
slang The S-Lang programing language
slsh Evaluate and run S-Lang code.
tips S-Lang tips and example functions
usermodel Creating Sherpa Usermodels with S-Lang
variables Variables in S-Lang

slangrtl abs Compute the absolute value of a number
acosh Compute the inverse cosh of an number
acos Compute the arc-cosine of an number
append_to_slang_load_path Append a directory to the load-path
array_info Returns information about an array
array_map Apply a function to each element of an array
array_sort Sort an array
array_to_bstring Convert an array to a binary string
asinh Compute the inverse-sinh of an number
asin Compute the arc-sine of an number
assoc_delete_key Delete a key from an Associative Array
assoc_get_keys Return all the key names of an Associative Array
assoc_get_values Return all the values of an Associative Array
assoc_key_exists Check to see whether a key exists in an Associative Array
atanh Compute the inverse-tanh of an number
atan Compute the arc-tangent of an number
atof Convert a string to a double precision number
autoload Load a function from a file
bstring_to_array Convert a binary string to an array of characters
bstrlen Get the length of a binary string
byte_compile_file Compile a file to byte-code for faster loading.
char Convert an ascii value into a string
chdir Change the current working directory.
chmod Change the mode of a file
chown Change the owner of a file
clearerr Clear the error of a file stream
close Close an open file descriptor
Conj Compute the complex conjugate of a number
cosh Compute the hyperbolic cosine of an number
cos Compute the cosine of an number
create_delimited_string Concatenate strings using a delimiter
ctime Convert a calendar time to a string
cumsum Compute the cumulative sum of an array
current_namespace Get the name of the current namespace
define_case Define upper-lower case conversion.
double Convert an object to double precision
dup_fd Duplicate a file descriptor
dup Duplicate the value at the top of the stack
errno_string Return a string describing an errno.
errno Error code set by system functions.
error Generate an error condition
evalfile Interpret a file containing S-Lang code.
eval Interpret a string as S-Lang code
exch Exchange two items on the stack
exp Compute the exponential of an number
extract_element Extract the nth element of a string with delimiters
fclose Close a file
fdopen Convert a FD_Type file descriptor to a stdio File_Type object
feof Get the end-of-file status
ferror Determine the error status of an open file descriptor
fflush Flush an output stream
fgetslines Read all the lines from an open file
fgets Read a line from a file.
fileno Convert a stdio File_Type object to a FD_Type descriptor
fopen Open a file
fprintf Create and write a formatted string to a file
fputs Write a string to an open stream
fread Read binary data from a file
fseek Reposition a stream
ftell Obtain the current position in an open stream
fwrite Write binary data to a file
getcwd Get the current working directory
getegid Get the effective group id
getenv Get the value of an environment variable
geteuid Get the effective user-id of the current process
getgid Get the group id
getpid Get the current process id
getppid Get the parent process id
getuid Get the user-id of the current process
get_doc_string_from_file Read documentation from a file
get_import_module_path Get the search path for dynamically loadable objects
get_slang_load_path Get the value of the interpreter's load-path
get_struct_field_names Retrieve the field names associated with a structure
get_struct_field Get the value associated with a structure field
gmtime Break down a time in seconds to GMT timezone
Imag Compute the imaginary part of a number
implements Name a private namespace
import Dynamically link to a specified module
init_char_array Initialize an array of characters
integer Convert a string to an integer
int Typecast an object to an integer
isatty Determine if an open file descriptor refers to a terminal
isdigit Tests for a decimal digit character
is_defined Indicate whether a variable or function defined.
is_list_element Test whether a delimited string contains a specific element
is_struct_type Determine whether or not an object is a structure
is_substr Test for a specified substring within a string.
kill Send a signal to a process
length Get the length of an object
listdir Get a list of the files in a directory
localtime Break down a time in seconds to local timezone
log10 Compute the base-10 logarithm of an number
log Compute the logarithm of an number
lseek Reposition a file descriptor's file pointer
lstat_file Get information about a symbolic link
make_printable_string Format a string suitable for parsing
max Get the maximum value of an array
message Print a string onto the message device
min Get the minimum value of an array
mkdir Create a new directory
mkfifo Create a named pipe
mul2 Multiply a number by 2
open Open a file
pack Pack objects into a binary string
pad_pack_format Add padding to a pack format
path_basename Get the basename part of a pathname
path_concat Combine elements of a pathname
path_dirname Get the directory name part of a pathname
path_extname Return the extension part of a pathname
path_get_delimiter Get the value of a search-path delimiter
path_is_absolute Determine whether or not a pathname is absolute
path_sans_extname Strip the extension from a pathname
pclose Close an object opened with popen
polynom Evaluate a polynomial
popen Open a process
pop Discard an item from the stack
prepend_to_slang_load_path Prepend a directory to the load-path
printf Create and write a formatted string to stdout
provide Declare that a specified feature is available
putenv Add or change an environment variable
readlink Get the value of a symbolic link
read Read from an open file descriptor
Real Compute the real part of a number
remove Delete a file
rename Rename a file
require Make sure a feature is present, and load it if not
reshape Reshape an array
rmdir Remove a directory
setgid Set the group-id of the current process
setpgid Set the process group-id
setuid Set the user-id of the current process
set_float_format Set the format for printing floating point values.
set_import_module_path Set the search path for dynamically loadable objects
set_slang_load_path Set the value of the interpreter's load-path
set_struct_fields Set the fields of a structure
set_struct_field Set the value associated with a structure field
shift Shift the elements of a 1-d array
sign Compute the sign of a number
sinh Compute the hyperbolic sine of an number
sin Compute the sine of an number
sizeof_pack Compute the size implied by a pack format string
slangrtl S-Lang Run Time Library
sleep Pause for a specified number of seconds
sprintf Format objects into a string
sqrt Compute the square root of an number
sqr Compute the square of a number
sscanf Parse a formatted string
stat_file Get information about a file
stat_is Parse the st_mode field of a stat structure
strcat Concatenate strings
strchopr Chop or split a string into substrings.
strchop Chop or split a string into substrings.
strcmp Compare two strings
strcompress Remove excess whitespace characters from a string
string_match_nth Get the result of the last call to string_match
string_match Match a string against a regular expression
string Convert an object to a string representation.
strjoin Concatenate elements of a string array
strlen Compute the length of a string
strlow Convert a string to lowercase
strncmp Compare the first few characters of two strings
strreplace Replace one or more substrings
strsub Replace a character with another in a string.
strtok Extract tokens from a string
strtrans Replace characters in a string
strtrim_beg Remove leading whitespace from a string
strtrim_end Remove trailing whitespace from a string
strtrim Remove whitespace from the ends of a string
strup Convert a string to uppercase
str_delete_chars Delete characters from a string
str_quote_string Escape characters in a string.
str_replace Replace a substring of a string
str_uncomment_string Remove comments from a string
substr Extract a substring from a string
sum Sum over the elements of an array
system Execute a shell command
tanh Compute the hyperbolic tangent of an number
tan Compute the tangent of an number
tic Start timing
times Get process times
time Return the current data and time as a string
toc Get elapsed CPU time
tolower Convert a character to lowercase.
toupper Convert a character to uppercase.
transpose Transpose an array
typecast Convert an object from one data type to another.
typeof Get the data type of an object.
umask Set the file creation mask
uname Get the system name
unpack Unpack Objects from a Binary String
usage Generate a usage error
use_namespace Change to another namespace
verror Generate an error condition
vmessage Print a formatted string onto the message device
where Get indices where an integer array is non-zero
write Write to an open file descriptor
_apropos Generate a list of functions and variables
_auto_declare Set automatic variable declaration mode
_clear_error Clear an error condition
_debug_info Configure debugging information
_featurep Test whether or not a feature is present
_function_name Returns the name of the currently executing function
_get_namespaces Returns a list of namespace names
_isnull Check array for NULL elements
_NARGS The number of parameters passed to a function
_pop_n Remove objects from the stack
_print_stack print the values on the stack.
_push_struct_field_values Push the values of a structure's fields onto the stack
_reshape Copy an array to a new shape
_slangtrace Turn function tracing on or off.
_slang_doc_dir Installed documentation directory
_slang_guess_type Guess the data type that a string represents.
_slang_version_string The S-Lang library version number as a string
_slang_version The S-Lang library version number
_stkdepth Get the number of objects currently on the stack.
_stk_reverse Reverse the order of the objects on the stack.
_stk_roll Roll items on the stack
_time Get the current time in seconds
_traceback Generate a traceback upon error
_trace_function Set the function to trace
_typeof Get the data type of an object
__class_id Return the class-id of a specified type
__class_type Return the class-type of a specified type
__eqs Test for equality between two objects
__get_defined_symbols Get the symbols defined by the preprocessor
__get_reference Get a reference to a global object
__is_initialized Determine whether or not a variable has a value
__pop_args Remove n function arguments from the stack
__push_args Remove n function arguments onto the stack
__uninitialize Uninitialize a variable

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 (1) Extract source and/or background ACIS imaging spectra for both point-like and extended sources; (2) coadd ACIS spectra; (3) 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 (L1)
acis_expmap Generate ACIS exposure maps for celldetect recursive blocking
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 paremeters of the ardlib file to the given file
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.
analyze_ltcrv analyze_ltcrv.sl - An algorithm for cleaning lightcurves
apowerspectrum Compute the power spectrum of an N-dimensional input array, or from two columns (independent/dependent variable) in an input file
arestore restore image resolution using deconvolution techniques
ascii2fits Convert simple ASCII files to FITS format files
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.
celldetect Use a "sliding cell" to search for sources
chart_spectrum chart_spectrum.sl - Create a source spectrum for input to ChaRT
color_image Run dmimg2jpg to make a color JPEG image
csmooth Adaptively smooth a 2-D image
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 FITS files.
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
dmimgcalc Perform arithmetic on images
dmimghist Create a histogram of the pixel values in a 2-D image
dmimgpick Maps image values to rows in a table
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
dmmerge Merge two or more compatible tables (e.g. event files) into one.
dmpaste Add new columns to a table.
dmreadpar Create header keywords from a parameter file
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 output file for specified rows of a type 2 file.
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
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.
lc_clean lc_clean.sl - Clean a lightcurve to match the ACIS "blank-sky" datasets
lightcurve Bin source and background events by specified time intervals
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)
mkoif Create an OIF (observation index file) for a dataset
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
monitor_photom Generate a photometric lightcurve from ACA monitor 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
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
quizcaldb Find calibration files in the CALDB
regions regions.sl - Display the FEF regions covered by a source
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 (or stack) to a common 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
show_tgain_corr Display the time-dependent gain correction for a given chip location.
show_wgt show_wgt.sl - Examine the weights file created by mkwarf
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.
spectrum spectrum.sl - Calculate spectral weights for creating an instrument map
sso_freeze Reproject sky x and y coordinates into a Solar System Object centered reference frame.
sstats sstats.sl- Calculate statistics of images
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
syntax Syntax used for writing mathematical operations in dmtcalc, dmimgcalc, and dmgti
tgdetect Detect and centroid the zero order image in a spatial sub-region of a grating event list.
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_osort_img Create an image that shows the density of events in different orders
tg_resolve_events Assign grating events to spectral orders; use detector energy resolution for order separation, if available.
tg_scale_reg Create a region file that labels distances along the grating arm
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

varmm apropos S-Lang function to find defined symbols (functions and variables)
clearstack S-Lang function to clear the stack.
dup_struct S-Lang function to duplicate a structured variable.
fits_bitpix Converts S-Lang variables and data types to FITS BITPIX values.
is_struct_defined S-Lang function to see if a structure or field in a structure is defined
print S-Lang functions to print variables, arrays and structures
readarf S-Lang function to read an Ancillary Response File (ARF)
readascii S-Lang function to read in an ASCII data file.
readbintab S-Lang function to read a FITS binary table.
readfile S-Lang functions to read a data file into a S-Lang variable.
readimage S-Lang function to read a FITS image.
readpha S-Lang function to read a spectrum in PHA format (both type I and II)
readrdb S-Lang function to read a file in RDB format.
readrmf S-Lang function to read a Redistribution Matrix File (RMF)
reverse S-Lang function to reverse a 1D array
set_state_defaults Restore the default values of state (configuration) variables
set_state Set multiple fields of a state (configuration) variable
username Returns the login name of the owner of the current process.
writeascii S-Lang function to create an ASCII output file from S-Lang arrays
writefits S-Lang function to create a FITS output file.
__exit S-Lang function to abort applications.

varmmrl varmm_rl_blink Sets the "blink" mode of the ChIPS and Sherpa command line.
varmm_rl_editmode Set the editing mode ("emacs" or "vi") of the ChIPS and Sherpa command line.

xpa slxpa_errno This variable stores the error status for the XPA commands.
xpaaccess Find out how many XPA access points are available that match a given name.
xpaclose Close a persistent XPA connection created by XPAOpen().
xpagetb Retrieve binary data from one or more XPA servers.
xpagettofile Retrieve data from one or more XPA servers and write the results to a file.
xpaget Retrieve data from one or more XPA servers.
xpaopen Create a persistent connection for XPA calls.
xpaset Send a command or data to one or more XPA servers.
xpa_maxhosts This variable stores the maximum number of hosts to be contacted in a XPA call.
xpa_version The version of the XPA library being used by the S-Lang module.
_slxpa_version The version of the S-Lang XPA module.

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Last modified: 23 March 2007



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