Last modified: 13 December 2018

Alphabetical List of Ahelp Files


    Topic Context Summary
A absorptionedge models Optical model of an absorption edge.
absorptiongaussian models Gaussian function for modeling absorption (equivalent width).
absorptionlorentz models Lorentz function for modeling absorption (equivalent width).
absorptionvoigt models Voigt function for modeling absorption (equivalent width).
accretiondisk models A model of emission due to an accretion disk.
add_model modeling Add a user-defined model class as a Sherpa model type
add_user_pars modeling Add parameters to a user-defined model
atten models Model the attenuation by the Inter-Stellar Medium (ISM).

B bbodyfreq models A one-dimensional Blackbody model (frequency).
bbody models A one-dimensional Blackbody model.
beta1d models One-dimensional beta model function.
beta2d models Two-dimensional beta model function.
blackbody models Emission from a black body as a function of wavelength.
box1d models One-dimensional box function.
box2d models Two-dimensional box function.
bpl1d models One-dimensional broken power-law function.
bremsstrahlung models Bremsstrahlung emission.
brokenpowerlaw models Broken power-law model.

C calc_chisqr utilities Calculate the Chi Squared statistic contribution per bin
calc_data_sum2d utilities Calculate the sum of observed image counts
calc_data_sum utilities Calculate the sum of observed data counts
calc_energy_flux utilities Calculate the unconvolved model energy flux
calc_ftest utilities Calculate the significance using the F test
calc_kcorr utilities Calculate the k correction for a spectral model.
calc_mlr utilities Calculate the Maximum Likelihood Ratio test
calc_model_sum2d utilities Calculate the convolved 2D model amplitudes
calc_model_sum utilities Calculate the sum of convolved model counts
calc_photon_flux utilities Calculate the unconvolved model photon flux
calc_source_sum2d utilities Calculate the unconvolved 2D model amplitudes
calc_source_sum utilities Calculate the sum of unconvolved model amplitudes
calc_stat_info fitting Returns goodness-of-fit statistics associated with a Sherpa data set.
calc_stat utilities Calculate the fit statistic by data set ID
cash statistics A maximum likelihood function.
ccm models Galactic extinction: the Cardelli, Clayton, and Mathis model.
chi2constvar statistics Chi-square statistic with constant variance computed from the counts data.
chi2datavar statistics Chi-square statistic with variance computed from the data.
chi2gehrels statistics Chi-square statistic with the Gehrels variance function.
chi2modvar statistics Chi-square statistic with variance computed from model amplitudes.
chi2xspecvar statistics Chi-square statistic with variance computed from data amplitudes.
chisquare statistics About the chi-square statistic.
clean modeling Erase data and model settings in a Sherpa session
conf confidence Estimate confidence intervals for selected thawed parameters based on confidence method
const1d models A constant model for one-dimensional data.
const2d models A constant model for two-dimensional data.
contour_data visualization Open a contour plot of a data set in ChIPS
contour_fit_resid visualization Create a contour plot of the fit and residuals
contour_fit visualization Send a contour plot of the fit
contour_kernel psfs Create a contour plot of a PSF kernel
contour_model visualization Open a contour plot of a data set model in ChIPS
contour_psf psfs Create a contour plot of a PSF
contour_ratio visualization Open a contour plot of a data-to-model ratio in ChIPS
contour_resid visualization Open a contour plot of data-minus-model residuals in ChIPS
contour_source visualization Create a contour plot of the source
contour visualization Open a contour plot in ChIPS
copy_data data Copy a data set by data ID to a new data ID (deep copy)
cos models One-dimensional cosine function.
covariance confidence Estimate confidence intervals for selected thawed parameters based on covariance method
create_model_component modeling Create a new model component
cstat statistics A maximum likelihood function from XSPEC

D dataspace1d data Create a blank 1D dataset
dataspace2d data Create a blank 2D dataset
datastack data Sherpa extension package for modeling stacks of data.
delete_bkg_model modeling Delete a background model
delete_data data Delete a data set by ID
delete_model_component modeling Delete a model component
delete_model modeling Delete a Sherpa model by model ID
delete_psf psfs Delete a PSF model
delta1d models One-dimensional delta function.
delta2d models Two-dimensional delta function.
dered models A de-reddening model.
devaucouleurs2d models Two-dimensional de Vaucouleurs model.
disk2d models Two-dimensional uniform disk model.

E edge models Photoabsorption edge model.
emissiongaussian models Gaussian function for modeling emission.
emissionlorentz models Lorentz function for modeling emission.
emissionvoigt models Voigt function for modeling emission.
eqwidth utilities Calculate the equivalent width of an emission or absorption line.
erfc models One-dimensional complementary error function.
erf models One-dimensional error function.
estimate_weighted_expmap contrib Return the estimated exposure map value by weighting an ARF by a spectral model.
exp10 models One-dimensional exponential function, base 10.
exp models One-dimensional exponential function.

F fake_pha data Simulate an observed spectrum based on a theoretical model.
fake data Simulate a generic data set with a chosen model and add noise
fit fitting Perform a fit using current optimization method and fit statistic.
fm models UV extinction curve: Fitzpatrick and Massa 1988.
freeze modeling Freeze model parameters, so they do not vary during a fit.

G gamma utilities Calculate the Gamma function
gauss1d models One-dimensional gaussian function.
gauss2d models Two-dimensional gaussian function.
get_analysis utilities Return the current units setting for a PHA data set
get_areascal data Return the source or background pixel fractional area scale
get_arf_plot data Return the data and preferences defining an ARF plot
get_arf data Return a source or background ARF by data set ID
get_axes data Return the alternate grid of a data set
get_backscal data Return the source or background extraction region area
get_bkg_plot data Return the data and preferences defining a background plot.
get_bkg_scale data Returns the complete background scaling factor
get_bkg data Return the background data, ARF, RMF, or model.
get_chart_spectrum contrib Return the model spectrum in the form required by ChaRT2
get_chisqr_plot statistics Return the data and preferences defining a chi^2 plot
get_conf confidence Return information regarding the confidence method.
get_coord data Return the coordinate system of an image
get_counts data Return the dependent variable array (e.g., counts) of a data set
get_covar confidence Return settings or results for the covariance method.
get_data_plot data Return a plot, contour, or image of the data, or the associated preferences
get_data_prof_prefs contrib The plot preferences for radial or elliptical profiles of imaging data.
get_data_prof contrib Return the data used to create the radial or elliptical profile of imaging data.
get_data data Return details of a Sherpa data set by ID.
get_default_id info Return the default data set ID in a Sherpa session.
get_delchi_plot statistics Return the data and preferences defining a delta chi plot
get_delchi_prof_prefs contrib The plot preferences for radial or elliptical profiles of the residuals (data - model)/error to imaging data.
get_delchi_prof contrib Return the data used to create the radial or elliptical profile of the residuals (data - model)/error to imaging data.
get_dep data Return the dependent variable array (e.g., counts) of a data set
get_dims data Return the length of the x-dimension of a data set
get_draws methods Run the pyBLoCXS MCMC-based algorithm using the current sampler.
get_energy_flux_hist plotting Calculate a histogram of a simulated energy flux probability distribution
get_error data Return the total errors on the counts of a data set
get_exposure data Return the exposure time for a source or background data set
get_filter filtering Return the filter of a data set
get_fit_prof contrib Return the data used to create the radial or elliptical profile of fits to imaging data.
get_fit fitting Return model fit information associated with a Sherpa data set.
get_grouping data Obtain the grouping flags from a data set
get_indep data Return the independent variable array of a data set
get_instmap_weights contrib Return the model spectrum in the form required by the spectrumfile parameter of mkinstmap
get_int_proj confidence Return the confidence data defining an interval projection plot
get_int_unc confidence Return the confidence data defining an int_unc() plot
get_iter_method_name methods Return the name of the current iterative fitting method
get_iter_method_opt methods Return the value of the specified option for the current iterative fitting method
get_kernel psfs Return kernel plot, image, and contour preferences.
get_lrt_plot plotting Access a histogram plot of likelihood ratio test results.
get_lrt_results plotting Access the simulation results of the likelihood ratio test.
get_marx_spectrum contrib Return the model spectrum in the form required by MARX
get_method methods Return information on the optimization method
get_model_autoassign_func modeling Return the method for storing model identifiers
get_model_component_image modeling Returns the 2D data and coordinate settings defining the convolved model component image
get_model_component_plot modeling Returns the data and preferences defining the convolved model component plot
get_model_component modeling Returns the parameters for the specified model component
get_model_plot modeling Return a plot, contour, or image of a model, or the associated preferences
get_model_prof_prefs contrib The plot preferences for radial or elliptical profiles of the model (after any PSF convolution) for imaging data.
get_model_prof contrib Return the data used to create the radial or elliptical profile of the source model (after any PSF convolution) for imaging data.
get_model modeling Return the model, model parameters, or model type
get_num_par modeling Returns the number of parameters (total, frozen, or thawed) in a model.
get_order_plot modeling Return the data and preferences defining a plot of model spectral orders
get_par modeling Returns a model parameter.
get_photon_flux_hist plotting Calculate a histogram of a simulated photon flux probability distribution
get_pileup_model modeling Return the pileup model associated with a data set.
get_prior statistics Access the prior function associated with a Sherpa model parameter.
get_proj confidence Return information regarding the projection method.
get_psf psfs Return PSF model data and plot, image, and contour preferences.
get_pvalue_plot plotting Access a histogram plot of likelihood ratio test results.
get_pvalue_results plotting Access the simulation results of the likelihood ratio test.
get_quality data Obtain the quality flags from a data set
get_rate utilities Return the measured count rate of a data set
get_ratio visualization Return information on the ratio of data and model.
get_reg_proj confidence Return the confidence data defining a region projection contour plot
get_reg_unc confidence Return the confidence data defining a reg_unc() contour plot
get_resid_prof_prefs contrib The plot preferences for radial or elliptical profiles of the residuals (data - model) to imaging data.
get_resid_prof contrib Return the data used to create the radial or elliptical profile of the residuals (data - model) to imaging data.
get_resid visualization Return information on a contour plot of the residuals of data and model.
get_response modeling Get the associated instrument response model of a PHA data set by data ID
get_rmf data Return a source or background RMF by data set ID
get_sampler statistics Return information on the current pyBLoCXS sampler.
get_source_component_image modeling Returns the 2D data and coordinate settings defining the unconvolved model component image
get_source_component_plot modeling Returns the data and preferences defining the unconvolved model component plot
get_source_prof_prefs contrib The plot preferences for radial or elliptical profiles of the source model for imaging data.
get_source_prof contrib Return the data used to create the radial or elliptical profile of the source model (before any PSF convolution) for imaging data.
get_source modeling Return the unconvolved model associated with a Sherpa data set ID.
get_specresp data Return the effective area of a PHA spectrum
get_split_plot plotting Return plot attributes for multiple plots
get_staterror data Return the statistical errors on the counts of a data set
get_stat_info fitting Parses the goodness-of-fit statistic information returned by calc_stat_info()
get_stat statistics Return information on the fit statistic
get_syserror data Return the systematic errors on the counts of a data set
gridsearch methods Grid searching optimization method
group data Enable and specify the grouping settings of a spectral data set
guess modeling Estimate initial parameter values and ranges

H histogram1d visualization Create a 1D histogram from a binned grid and array of samples
histogram2d visualization Create a 2D histogram from a pair of axes and a pair of sample arrays
hubblereynolds models Two-dimensional Hubble-Reynolds model.

I igamc utilities Calculate the complement of the regularized incomplete Gamma function (upper)
igam utilities Calculate the regularized incomplete Gamma function (lower)
ignore2d_id filtering Apply an exclude region filter to 2-D data by data set ID(s).
ignore2d filtering Apply an exclude region filter to all 2-D data sets
ignore_bad filtering Ignore bins according to quality flags
ignore_id filtering Apply an exclude filter to 1-D data by data set ID
ignore filtering Apply an exclude filter to all 1D data sets
image_close visualization Close the imager window (i.e., exit ds9).
image_data visualization Send image of 2-D data to ds9.
image_deleteframes visualization Delete frames in the imager window (ds9).
image_fit visualization Send image of the fit results to ds9.
image_getregion visualization Returns a region description from ds9.
image_kernel psfs Send a PSF kernel image to the imager (ds9).
image_model_component modeling Sends image of the convolved model component to ds9.
image_model modeling Send image of the model to ds9.
image_open visualization Open the imager window (i.e., start ds9).
image_psf psfs Send a PSF image to the imager (ds9).
image_ratio visualization Send image of the ratio (i.e., data/model) to ds9.
image_resid visualization Send image of the residuals (i.e., data - model) to ds9.
image_setregion visualization Sends a region description to ds9, where it is drawn in the current frame.
image_source_component modeling Sends image of the unconvolved model component to ds9.
image_source modeling Image the 2-D unconvolved model
image_xpaget visualization Retrieve data from ds9 using XPA.
image_xpaset visualization Send data to ds9 using XPA.
incbet utilities Calculate the incomplete Beta function
integrate1d modeling <Integrate1D model type>
integrate modeling Controlling the integration of model components
int_proj confidence Create a confidence plot of fit statistic vs. parameter value.
int_unc confidence Create a confidence plot of fit statistic vs. parameter value.

J jdpileup models A CCD pileup model for the ACIS detectors on Chandra.

L leastsq statistics Chi-square statistic with variance set to 1.
levmar methods Levenberg-Marquardt optimization method
lgam utilities Calculate the log of the Gamma function
linebroad models A one-dimensional line-broadening profile.
link modeling Link a model parameter to another model parameter.
list_bkg_ids info List all background IDs associated with a data set.
list_data_ids info List all data set IDs in a Sherpa session.
list_functions info List all available Sherpa functions
list_iter_methods methods List all Sherpa iterative fitting methods.
list_methods methods List all Sherpa optimization methods.
list_models models List all Sherpa models.
list_model_components models List all models established in a Sherpa session.
list_model_ids info List all current model IDs.
list_priors statistics List thawed Sherpa model parameters with associated priors.
list_response_ids info List all response IDs associated with a data set.
list_samplers statistics List all available pyBLoCXS samplers.
list_stats info List all Sherpa fit statistics.
lmc models LMC extinction: the Howarth model.
lmod contrib Load a X-Spec local model, compiled with convert_xspec_user_model, into Sherpa
load_arf data Load a source or background ARF
load_arrays data Load data from variables containing arrays.
load_ascii data Load ASCII data
load_bkg_arf data Load a background ARF
load_bkg_rmf data Load a background RMF
load_bkg data Load a PHA background spectrum
load_conv psfs Load a 1D convolution kernel
load_data data Load 1D data from a file
load_filter filtering Load filter from a FITS table, FITS image, or ASCII file
load_grouping data Load a grouping scheme from a FITS table or ASCII file
load_image data Load an image
load_multi_arfs data Load multiple ARFs
load_multi_rmfs data Load multiple RMFs
load_pha data Load PHA source spectra
load_psf psfs Load a PSF model
load_quality data Load quality flags from a FITS table or ASCII file
load_rmf data Load a source or background RMF
load_staterror data Load statistical errors
load_syserror data Load systematic errors
load_table_model modeling Load a table model, including X-Spec atable and mtable forms
load_table data Load tabular data
load_template_model modeling Load a set of template models
load_user_model modeling Load a user-defined model
load_user_stat statistics Load a user-defined fit statistic
load_xscflux models calculate flux. XSpec convolution model *Experimental*.
load_xsclumin models calculate luminosity. XSpec convolution model *Experimental*.
load_xscpflux models calculate photon flux. XSpec convolution model *Experimental*.
load_xsgsmooth models gaussian smoothing. XSpec convolution model *Experimental*.
load_xsireflect models reflection from ionized material. XSpec convolution model *Experimental*.
load_xskdblur2 models convolve with the laor2 model shape. XSpec convolution model *Experimental*.
load_xskdblur models convolve with the laor model shape. XSpec convolution model *Experimental*.
load_xskerrconv models accretion disk line shape with BH spin as free parameter. XSpec convolution model *Experimental*.
load_xslsmooth models lorentzian smoothing. XSpec convolution model *Experimental*.
load_xspartcov models partial covering. XSpec convolution model *Experimental*.
load_xsrdblur models convolve with the dislkine model shape. XSpec convolution model *Experimental*.
load_xsreflect models reflection from neutral material. XSpec convolution model *Experimental*.
load_xsrfxconv models angle-dependent reflection from an ionized disk. XSpec convolution model *Experimental*.
load_xsrgsxsrc models convolve an RGS spectrum for extended emission. XSpec convolution model *Experimental*.
load_xssimpl models comptonization of a seed spectrum. XSpec convolution model *Experimental*.
load_xsvashift models Velocity shift an additive model. XSpec convolution model *Experimental*.
load_xsvmshift models Velocity shift a multiplicative model. XSpec convolution model *Experimental*.
load_xsxilconv models angle-dependent reflection from an ionized disk XSpec convolution model *Experimental*.
load_xszashift models Redshift an additive model. XSpec convolution model *Experimental*.
load_xszmshift models Redshift a multiplicative model. XSpec convolution model *Experimental*.
log10 models One-dimensional logarithm function, base 10.
logabsorption models Gaussian function for modeling absorption (log of fwhm).
logemission models Gaussian function for modeling emission (log of fwhm).
logparabola models One-dimensional log-parabolic function.
log models One-dimensional natural logarithm function.
lorentz1d models One-dimensional normalized Lorentz model function.
lorentz2d models Two-dimensional un-normalised Lorentz function.

M models models Summary of Sherpa models (excluding XSPEC)
moncar methods Monte Carlo optimization method

N neldermead methods Nelder-Mead Simplex optimization method
normal_sample modeling Sample the current set of thawed parameters from a uni-variate or multi-variate normal distribution.
normbeta1d models One-dimensional normalized beta model function.
normgauss1d models One-dimensional normalised gaussian function.
normgauss2d models Two-dimensional normalised gaussian function.
notice2d_id filtering Apply an include filter to 2D data by dataset id
notice2d filtering Apply an include filter to all 2D datasets
notice_id filtering Apply an include filter to 1D data by dataset id
notice filtering Apply an include filter to all 1D datasets

O opticalgaussian models Gaussian function for modeling absorption (optical depth).

P pack_image data Pack image data into an IMAGECrate
pack_pha data Pack PHA data into a PHACrate
pack_table data Pack tabular data into a TABLECrate
paramprompt modeling Toggle parameter prompting for initial model values
plot_arf plotting Plot an ARF
plot_bkg plotting Plot information about background data
plot_cdf plotting Plot a cumulative distribution function with lower, median, and upper quantiles.
plot_chart_spectrum contrib Plot up the model spectrum in the form required by ChaRT
plot_chisqr plotting Plot the chi-squared statistic
plot_data plotting Plot the dataset
plot_delchi plotting Plot the delchi residuals of the fit: (data-model)/error
plot_energy_flux plotting Plot the calculated energy flux distribution
plot_fit plotting Plot the fit, fit plus delta chi, or fit plus residuals
plot_instmap_weights contrib Plot up the model spectrum in the form required by mkinstmap
plot_kernel psfs Plot the PSF kernel
plot_marx_spectrum contrib Plot up the model spectrum in the form required by MARX
plot_model_component plotting Plots individual convolved source model components
plot_model plotting Plot the convolved source model
plot_order plotting Plot the convolved source model by order
plot_pdf plotting Plot a binned probability density function.
plot_photon_flux plotting Plot the calculated photon flux distribution
plot_psf psfs Plot the PSF
plot_pvalue plotting Plot a histogram of likelihood ratio test results.
plot_ratio plotting Plot the (data/model) ratio
plot_resid plotting Plot the residuals of the fit: (data - model)
plot_scatter plotting Create an X,Y scatter plot.
plot_source_component plotting Plots individual unconvolved source model components
plot_source plotting Plot the unconvolved source model
plot_trace plotting Create a trace plot of iteration number vs. sampled value.
plot plotting Plot multiple objects (data, model, residuals, etc.)
poisson models One-dimensional Poisson function.
polynom1d models One-dimensional polynomial function of order 8.
polynom2d models Two-dimensional polynomial function.
polynomial models Polynomial model of order 5.
powerlaw models Power-law model.
powlaw1d models One-dimensional power-law function.
prof_data contrib Plot a radial or elliptical profile of imaging data.
prof_delchi contrib Plot a radial or elliptical profile of the residuals (data - model)/error to imaging data.
prof_fit_delchi contrib Plot a radial or elliptical profile of the fit (data and model) and residuals (data-model)/error to imaging data.
prof_fit_resid contrib Plot a radial or elliptical profile of the fit (data and model) and residuals (data-model) to imaging data.
prof_fit contrib Plot a radial or elliptical profile of the fit (data and model) to imaging data.
prof_model contrib Plot a radial or elliptical profile of the model (after any PSF convolution) for imaging data.
prof_resid contrib Plot a radial or elliptical profile of the residuals (data - model) to imaging data.
prof_source contrib Plot a radial or elliptical profile of the source model for imaging data.
projection confidence Estimate confidence intervals for selected thawed parameters based on projection method
pyblocxs methods MCMC-based algorithm for Bayesian Low-Count X-ray Spectral (BLoCXS) analysis

R rebin visualization Rebin a histogram
recombination models Optically-thin recombination continuum model.
reg_proj confidence Create a confidence contour of fit statistic vs. two thawed parameter values.
reg_unc confidence Create a confidence contour of fit statistic vs. two thawed parameter values.
renorm contrib Change the normalization of a model to match the data.
reset modeling Reset model parameter values after a fit
restore saving Restore a previous Sherpa session from a file

S sample_energy_flux utilities Sample the energy flux distribution
sample_flux utilities Return a sample of Sherpa model parameters and the corresponding unabsorbed energy flux and flux uncertainty
sample_photon_flux utilities Sample the photon flux distribution
save_all saving Save all the information about the current session
save_arrays saving Save a list of arrays as columns to a FITS table or ASCII file
save_chart_spectrum contrib Write out the model spectrum in the form required by ChaRT2
save_data saving Save a Sherpa data set to an ASCII file.
save_delchi saving Save the delta chi fit residuals to a FITS table or ASCII file
save_error saving Save total errors to a FITS table or ASCII file
save_filter saving Save filter to a FITS table or ASCII file
save_grouping saving Save grouping flags to a FITS table or ASCII file
save_image saving Save image data to a file
save_instmap_weights contrib Write out the model spectrum in the form required by mkinstmap
save_marx_spectrum contrib Write out the model spectrum in the form required by MARX
save_model modeling Save the convolved source model to a FITS table or ASCII file
save_pha saving Save a Sherpa data set to a PHA file.
save_quality saving Save quality flags to a FITS table or ASCII file
save_resid saving Save the simple data-model difference residuals
save_source modeling Save the unconvolved source model to a FITS table or ASCII file
save_staterror saving Save statistical errors to a FITS table or ASCII file
save_syserror saving Save systematic errors to a FITS table or ASCII file
save_table saving Save a Sherpa data set to a FITS or ASCII file.
save saving Save the current Sherpa session to a file
scale1d models A constant model for one-dimensional data.
scale2d models A constant model for two-dimensional data.
schechter models One-dimensional Schecter model function.
script saving Save every command typed in a Sherpa or ChIPS session to a file.
seaton models Galactic extinction: the Seaton model from Synphot.
sersic2d models Two-dimensional Sersic model.
set_analysis utilities Set the units for spectral analysis
set_areascal data Set the fractional area
set_arf data Set an ARF dataset
set_backscal data Set the extraction region area
set_bkg_model modeling Set a background model expression
set_bkg data Set a background PHA dataset
set_conf_opt confidence Set the options for confidence
set_coord data Set the image coordinate system
set_counts data Set the dependent variable (e.g. counts) of a dataset
set_covar_opt confidence Set the options for covariance
set_data data Set a source dataset
set_default_id utilities Set the default Sherpa data id
set_exposure data Set the exposure time
set_filter filtering Apply user-defined filter to a data set
set_full_model modeling Set the complete convolved source and background model expressions to be used for fitting a data set
set_grouping data Apply user-defined grouping to a dataset
set_iter_method_opt methods Set the value of the specified option for the current iterative fitting method
set_iter_method methods Set the iterative fitting method
set_method_opt methods Set the options of the chosen optimization method
set_method methods Set the optimization method
set_model_autoassign_func modeling Define a method for storing model identifiers
set_par modeling Set initial values for a model parameter
set_pileup_model modeling Set a pileup model to be used in fitting a dataset
set_prior statistics Define a prior function for a particular Sherpa model parameter.
set_proj_opt confidence Set the options for projection
set_psf psfs Convolve the PSF model with the source model
set_quality data Apply user-defined quality flags to a data set
set_rmf data Set an RMF dataset
set_sampler_opt statistics Define sampler options for a pyBLoCXS chain.
set_sampler statistics Set the current pyBLoCXS sampler.
set_source modeling Set the source model expression to be used for fitting a dataset
set_staterror data Set the statistical errors
set_stat statistics Set the statistical method
set_syserror data Set the systematic errors
set_xlinear plotting Changes the plot X axis to use a linear scale.
set_xlog plotting Changes the plot x axis to use a logarithmic scale.
set_xsabund modeling Set XSPEC solar abundance
set_xscosmo modeling Set XSPEC cosmology settings (H0, q0, L0)
set_xsxsect modeling Set XSPEC photoelectric cross-section
set_xsxset modeling Set and get environment variables for XSPEC models
set_ylinear plotting Changes the plot Y axis to use a linear scale.
set_ylog plotting Changes the plot Y axis to use a logarithmic scale.
shell2d models A homogenous spherical 3D shell projected onto 2D.
sherparc sherpa The .sherpa.rc file provides user-configuration options for Sherpa
sherpa_chart contrib Create and view spectral files for ChaRT2 (CIAO contributed package).
sherpa_contrib contrib Contributed CIAO routines for Sherpa.
sherpa_marx contrib Create and view spectral files for MARX (CIAO contributed package).
sherpa_profiles contrib Radial profiles of imaging data in Sherpa (CIAO contributed package).
sherpa_utils contrib Utility routines for Sherpa (CIAO contributed package).
sherpa sherpa Introduction to Sherpa, the CIAO modeling and fitting package
show_all info Reports the current state of the Sherpa session
show_bkg_model info Display the background convolved model
show_bkg_source info Display the background unconvolved model
show_bkg info Display PHA background data set information
show_conf info Display the confidence information
show_covar info Display the covariance information
show_data info Display the data sets
show_filter filtering Display the filters applied to a dataset
show_fit info Display the fit information
show_kernel psfs Display the PSF kernel
show_method info Display the optimization method
show_model info Display the convolved source model
show_proj info Display the projection information
show_psf psfs Display the PSF model
show_source info Display the unconvolved source model
show_stat info Display the fit statistic
sigmagauss2d models Two-dimensional gaussian function (varying sigma).
sin models One-dimensional sine function.
smc models SMC extinction: the Prevot et al. 1984 model.
sm models Galactic extinction: the Savage & Mathis model.
sqrt models One-dimensional square root function.
stephi1d models One-dimensional step function.
steplo1d models One-dimensional step function.
subtract data Perform background subtraction

T tablemodel models Using an n-dimensional array of values as a model (table model).
tan models One-dimensional tan function.
thaw modeling Thaw model parameters so they vary during a fit
t_sample modeling Sample the current set of thawed parameters from a Student's t-distribution.

U ungroup data Ungroup PHA data
uniform_sample modeling Sample the current set of thawed parameters from a uniform distribution.
unlink modeling Remove a link between model parameters
unpack_arf data Unpack an ARF from an ARFCrate
unpack_arrays data Unpack arrays from a CrateData object
unpack_ascii data Unpack ASCII data from a crate
unpack_bkg data Unpack PHA data from a PHACrate
unpack_data data Unpack a table data, ASCII data, or a spectrum from a crate
unpack_image data Unpack image data from an IMAGECrate
unpack_pha data Unpack PHA data from a PHACrate
unpack_rmf data Unpack an RMF from a crate
unpack_table data Unpack tabular data from a TABLECrate
unsubtract data Undo background subtraction

W wstat statistics A maximum likelihood function from XSPEC

X xgal models Extragalactic extinction: Calzetti, Kinney and Storchi-Bergmann
xsabsori models The XSPEC absori model: ionized absorber.
xsacisabs models The XSPEC acisabs model: Chandra ACIS q.e. decay.
xsagauss models The XSPEC agauss model: gaussian line profile in wavelength space.
xsapec models The XSPEC apec model: APEC emission spectrum.
xsbapec models The XSPEC bapec model: velocity broadened APEC thermal plasma model.
xsbbodyrad models The XSPEC bbodyrad model: blackbody spectrum, area normalized.
xsbbody models The XSPEC bbody model: blackbody spectrum.
xsbexrav models The XSPEC bexrav model: reflected e-folded broken power law, neutral medium.
xsbexriv models The XSPEC bexriv model: reflected e-folded broken power law, ionized medium.
xsbkn2pow models The XSPEC bkn2pow model: broken power law with two breaks.
xsbknpower models The XSPEC bknpower model: broken power law.
xsbmc models The XSPEC bmc model: Comptonization by relativistic matter.
xsbremss models The XSPEC bremss model: thermal bremsstrahlung.
xsbrnei models The XSPEC brnei model: velocity-broadened non-equilibrium recombining collisional plasma.
xsbtapec models The XSPEC btapec model: velocity broadened APEC emission spectrum with separate continuum and line temperatures.
xsbvapec models The XSPEC bvapec model: velocity broadened APEC thermal plasma model.
xsbvrnei models The XSPEC bvrnei model: velocity-broadened non-equilibrium recombining collisional plasma.
xsbvtapec models The XSPEC bvtapec model: velocity broadened APEC emission spectrum with separate continuum and line temperatures.
xsbvvapec models The XSPEC bvvapec model: velocity broadened APEC thermal plasma model.
xsbvvrnei models The XSPEC bvvrnei model: velocity-broadened non-equilibrium recombining collisional plasma.
xsbvvtapec models The XSPEC bvvtapec model: velocity broadened APEC emission spectrum with separate continuum and line temperatures.
xsc6mekl models The XSPEC c6mekl model: differential emission measure using Chebyshev representations with multi-temperature mekal.
xsc6pmekl models The XSPEC c6pmekl model: differential emission measure using Chebyshev representations with multi-temperature mekal.
xsc6pvmkl models The XSPEC c6pvmkl model: differential emission measure using Chebyshev representations with multi-temperature mekal.
xsc6vmekl models The XSPEC c6vmekl model: differential emission measure using Chebyshev representations with multi-temperature mekal.
xscabs models The XSPEC cabs model: Optically-thin Compton scattering.
xscarbatm models The XSPEC carbatm model: Nonmagnetic carbon atmosphere of a neutron star.
xscemekl models The XSPEC cemekl model: plasma emission, multi-temperature using mekal.
xscevmkl models The XSPEC cevmkl model: plasma emission, multi-temperature using mekal.
xscflow models The XSPEC cflow model: cooling flow.
xscompbb models The XSPEC compbb model: Comptonization, black body.
xscompls models The XSPEC compLS model: Comptonization, Lamb & Sanford.
xscompmag models The XSPEC compmag model: Thermal and bulk Comptonization for cylindrical accretion onto the polar cap of a magnetized neutron star.
xscompps models The XSPEC compPS model: Comptonization, Poutanen & Svenson.
xscompst models The XSPEC compST model: Comptonization, Sunyaev & Titarchuk.
xscomptb models The XSPEC comptb model: Thermal and bulk Comptonization of a seed blackbody-like spectrum.
xscompth models The XSPEC compth model: Paolo Coppi's hybrid (thermal/non-thermal) hot plasma emission models.
xscomptt models The XSPEC compTT model: Comptonization, Titarchuk.
xsconstant models The XSPEC constant model: energy-independent factor.
xsconvolve models The XSpec convolution models *Experimental*.
xscplinear models The XSPEC cplinear model: a non-physical piecewise-linear model for low count background spectra.
xscutoffpl models The XSPEC cutoffpl model: power law, high energy exponential cutoff.
xscyclabs models The XSPEC cyclabs model: absorption line, cyclotron.
xsdiskbb models The XSPEC diskbb model: accretion disk, multi-black body components.
xsdiskir models The XSPEC diskir model: Irradiated inner and outer disk.
xsdiskline models The XSPEC diskline model: accretion disk line emission, relativistic.
xsdiskm models The XSPEC diskm model: accretion disk with gas pressure viscosity.
xsdisko models The XSPEC disko model: accretion disk, inner, radiation pressure viscosity.
xsdiskpbb models The XSPEC diskpbb model: accretion disk, power-law dependence for T(r).
xsdiskpn models The XSPEC diskpn model: accretion disk, black hole, black body.
xsdisk models The XSPEC disk model: accretion disk, black body.
xsdust models The XSPEC dust model: dust scattering.
xsedge models The XSPEC edge model: absorption edge.
xseplogpar models The XSPEC eplogpar model: log-parabolic blazar model with nu-Fnu normalization.
xseqpair models The XSPEC eqpair model: Paolo Coppi's hybrid (thermal/non-thermal) hot plasma emission models.
xseqtherm models The XSPEC eqtherm model: Paolo Coppi's hybrid (thermal/non-thermal) hot plasma emission models.
xsequil models The XSPEC equil model: collisional plasma, ionization equilibrium.
xsexpabs models The XSPEC expabs model: exponential roll-off at low E.
xsexpdec models The XSPEC expdec model: exponential decay.
xsexpfac models The XSPEC expfac model: exponential modification.
xsezdiskbb models The XSPEC ezdiskbb model: multiple blackbody disk model with zero-torque inner boundary.
xsgabs models The XSPEC gabs model: gaussian absorption line.
xsgadem models The XSPEC gadem model: plasma emission, multi-temperature with gaussian distribution of emission measure.
xsgaussian models The XSPEC gaussian model: gaussian line profile.
xsgnei models The XSPEC gnei model: collisional plasma, non-equilibrium, temperature evolution.
xsgrad models The XSPEC grad model: accretion disk, Schwarzschild black hole.
xsgrbcomp models The XSPEC grbcomp model: Comptonization for GRB prompt emission.
xsgrbm models The XSPEC grbm model: gamma-ray burst continuum.
xshatm models The XSPEC hatm model: Nonmagnetic hydrogen atmosphere of a neutron star.
xsheilin models The XSPEC heilin model: Voigt absorption profiles for He I series.
xshighecut models The XSPEC highecut model: high-energy cutoff.
xshrefl models The XSPEC hrefl model: reflection model.
xsismabs models The XSPEC ismabs model: A high resolution ISM absorption model with variable columns for individual ions.
xsjet models The XSPEC jet model: Leptonic relativistic jet model.
xskerrbb models The XSPEC kerrbb model: multi-temperature blackbody model for thin accretion disk around a Kerr black hole.
xskerrdisk models The XSPEC kerrdisk model: accretion disk line emission with BH spin as free parameter.
xskerrd models The XSPEC kerrd model: optically thick accretion disk around a Kerr black hole.
xslaor2 models The XSPEC laor2 model: accretion disk with broken-power law emissivity profile, black hole emission line.
xslaor models The XSPEC laor model: accretion disk, black hole emission line.
xslogpar models The XSPEC logpar model: log-parabolic blazar model.
xslorentz models The XSPEC lorentz model: lorentz line profile.
xslyman models The XSPEC lyman model: Voigt absorption profiles for H I or He II Lyman series.
xsmekal models The XSPEC mekal model: emission, hot diffuse gas (Mewe-Kaastra-Liedahl).
xsmeka models The XSPEC meka model: emission, hot diffuse gas (Mewe-Gronenschild).
xsmkcflow models The XSPEC mkcflow model: cooling flow, mekal.
xsnei models The XSPEC nei model: collisional plasma, non-equilibrium, constant temperature.
xsnlapec models The XSPEC nlapec model: continuum-only APEC emission spectrum.
xsnotch models The XSPEC notch model: absorption line, notch.
xsnpshock models The XSPEC npshock model: shocked plasma, plane parallel, separate ion, electron temperatures.
xsnsagrav models The XSPEC nsagrav model: NS H atmosphere model for different g.
xsnsatmos models The XSPEC nsatmos model: NS Hydrogen Atmosphere model with electron conduction and self-irradiation.
xsnsa models The XSPEC nsa model: neutron star atmosphere.
xsnsmaxg models The XSPEC nsmaxg model: neutron star with a magnetic atmosphere.
xsnsmax models The XSPEC nsmax model: Neutron Star Magnetic Atmosphere.
xsnsx models The XSPEC nsx model: neutron star with a non-magnetic atmosphere.
xsnteea models The XSPEC nteea model: non-thermal pair plasma.
xsnthcomp models The XSPEC nthComp model: Thermally comptonized continuum.
xsoptxagnf models The XSPEC optxagnf model: Colour temperature corrected disc and energetically coupled Comptonisation model for AGN.
xsoptxagn models The XSPEC optxagn model: Colour temperature corrected disc and energetically coupled Comptonisation model for AGN.
xspcfabs models The XSPEC pcfabs model: partial covering fraction absorption.
xspegpwrlw models The XSPEC pegpwrlw model: power law, pegged normalization.
xspexmon models The XSPEC pexmon model: neutral Compton reflection with self-consistent Fe and Ni lines.
xspexrav models The XSPEC pexrav model: reflected powerlaw, neutral medium.
xspexriv models The XSPEC pexriv model: reflected powerlaw, neutral medium.
xsphabs models The XSPEC phabs model: photoelectric absorption.
xsplabs models The XSPEC plabs model: power law absorption.
xsplcabs models The XSPEC plcabs model: powerlaw observed through dense, cold matter.
xsposm models The XSPEC posm model: positronium continuum.
xspowerlaw models The XSPEC powerlaw model: power law photon spectrum.
xspshock models The XSPEC pshock model: plane-parallel shocked plasma, constant temperature.
xspwab models The XSPEC pwab model: power-law distribution of neutral absorbers.
xsraymond models The XSPEC raymond model: emission, hot diffuse gas, Raymond-Smith.
xsredden models The XSPEC redden model: interstellar extinction.
xsredge models The XSPEC redge model: emission, recombination edge.
xsrefsch models The XSPEC refsch model: reflected power law from ionized accretion disk.
xsrnei models The XSPEC rnei model: non-equilibrium recombining collisional plasma.
xssedov models The XSPEC sedov model: sedov model, separate ion/electron temperature.
xssirf models The XSPEC sirf model: self-irradiated funnel.
xsslimbh models The XSPEC slimbh model: Stationary slim accretion disk.
xssmedge models The XSPEC smedge model: smeared edge.
xssnapec models The XSPEC snapec model: galaxy cluster spectrum using SN yields.
xsspexpcut models The XSPEC spexpcut model: super-exponential cutoff absorption.
xsspline models The XSPEC spline model: spline modification.
xssrcut models The XSPEC srcut model: synchrotron spectrum, cutoff power law.
xssresc models The XSPEC sresc model: synchrotron spectrum, cut off by particle escape.
xsssa models The XSPEC ssa model: Strangeon star atmosphere.
xssss_ice models The XSPEC sss_ice model: Einstein SSS ice absorption.
xsstep models The XSPEC step model: step function convolved with gaussian.
xsswind1 models The XSPEC swind1 model: absorption by partially ionized material with large velocity shear.
xstapec models The XSPEC tapec model: APEC emission spectrum with separate continuum and line temperatures.
xstbabs models The XSPEC TBabs model: ISM grain absorption.
xstbfeo models The XSPEC TBfeo model: ISM grain absorption.
xstbgas models The XSPEC TBgas model: ISM grain absorption.
xstbgrain models The XSPEC TBgrain model: ISM grain absorption.
xstbpcf models The XSPEC TBpcf model: ISM grain absorption.
xstbrel models The XSPEC TBrel model: ISM grain absorption.
xstbvarabs models The XSPEC TBvarabs model: ISM grain absorption.
xsuvred models The XSPEC uvred model: interstellar extinction, Seaton Law.
xsvapec models The XSPEC vapec model: APEC emission spectrum.
xsvarabs models The XSPEC varabs model: photoelectric absorption.
xsvbremss models The XSPEC vbremss model: thermal bremsstrahlung.
xsvequil models The XSPEC vequil model: collisional plasma, ionization equilibrium.
xsvgadem models The XSPEC vgadem model: plasma emission, multi-temperature with gaussian distribution of emission measure.
xsvgnei models The XSPEC vgnei model: collisional plasma, non-equilibrium, temperature evolution.
xsvmcflow models The XSPEC vmcflow model: cooling flow, mekal.
xsvmekal models The XSPEC vmekal model: emission, hot diffuse gas (Mewe-Kaastra-Liedahl).
xsvmeka models The XSPEC vmeka model: emission, hot diffuse gas (Mewe-Gronenschild).
xsvnei models The XSPEC vnei model: collisional plasma, non-equilibrium, constant temperature.
xsvnpshock models The XSPEC vnpshock model: shocked plasma, plane parallel, separate ion, electron temperatures.
xsvoigt models The XSPEC voigt model: Voigt line profile.
xsvphabs models The XSPEC vphabs model: photoelectric absorption.
xsvpshock models The XSPEC vpshock model: plane-parallel shocked plasma, constant temperature.
xsvraymond models The XSPEC vraymond model: emission, hot diffuse gas, Raymond-Smith.
xsvrnei models The XSPEC vrnei model: non-equilibrium recombining collisional plasma.
xsvsedov models The XSPEC vsedov model: sedov model, separate ion/electron temperature.
xsvtapec models The XSPEC vtapec model: APEC emission spectrum with separate continuum and line temperatures.
xsvvapec models The XSPEC vvapec model: APEC emission spectrum.
xsvvgnei models The XSPEC vvgnei model: collisional plasma, non-equilibrium, temperature evolution.
xsvvnei models The XSPEC vvnei model: collisional plasma, non-equilibrium, constant temperature.
xsvvnpshock models The XSPEC vvnpshock model: shocked plasma, plane parallel, separate ion, electron temperatures.
xsvvpshock models The XSPEC vvpshock model: plane-parallel shocked plasma, constant temperature.
xsvvrnei models The XSPEC vvrnei model: non-equilibrium recombining collisional plasma.
xsvvsedov models The XSPEC vvsedov model: sedov model, separate ion/electron temperature.
xsvvtapec models The XSPEC vvtapec model: APEC emission spectrum with separate continuum and line temperatures.
xswabs models The XSPEC wabs model: photoelectric absorption, Wisconsin cross-sections.
xswndabs models The XSPEC wndabs model: photo-electric absorption, warm absorber.
xsxion models The XSPEC xion model: reflected spectrum of photo-ionized accretion disk/ring.
xsxscat models The XSPEC xscat model: dust scattering.
xszagauss models The XSPEC zagauss model: gaussian line profile in wavelength space.
xszbabs models The XSPEC zbabs model: EUV ISM attenuation
xszbbody models The XSPEC zbbody model: blackbody spectrum.
xszbremss models The XSPEC zbremss model: thermal bremsstrahlung.
xszcutoffpl models The XSPEC zcutoffpl model: power law, high energy exponential cutoff.
xszdust models The XSPEC zdust model: extinction by dust grains.
xszedge models The XSPEC zedge model: absorption edge.
xszgauss models The XSPEC zgauss model: gaussian line profile.
xszhighect models The XSPEC zhighect model: high-energy cutoff.
xszigm models The XSPEC zigm model: UV/Optical attenuation by the intergalactic medium.
xszpcfabs models The XSPEC zpcfabs model: partial covering fraction absorption.
xszphabs models The XSPEC zphabs model: photoelectric absorption.
xszpowerlw models The XSPEC zpowerlw model: redshifted power law photon spectrum.
xszredden models The XSPEC zredden model: redshifted version of redden.
xszsmdust models The XSPEC zsmdust model: extinction by dust grains in starburst galaxies.
xsztbabs models The XSPEC zTBabs model: ISM grain absorption.
xszvarabs models The XSPEC zvarabs model: photoelectric absorption.
xszvfeabs models The XSPEC zvfeabs model: photoelectric absorption with free Fe edge energy.
xszvphabs models The XSPEC zvphabs model: photoelectric absorption.
xszwabs models The XSPEC zwabs model: photoelectric absorption, Wisconsin cross-sections.
xszwndabs models The XSPEC zwndabs model: photo-electric absorption, warm absorber.
xszxipcf models The XSPEC zxipcf model: partial covering absorption by partially ionized material.
xs models XSPEC model functions.