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Last modified: 3 November 2009

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Python ahelp files for Sherpa 4.1
Alphabetical List

Jump to: Main AHELP page | S-Lang Alphabetical List | Contextual List

A B C D E F G H I J L M N P R S T U X

    Topic Summary
A add_user_pars Add parameters to a user-defined model
atten Attenuation by ISM.
B bbodyfreq Blackbody as a function of frequency.
bbody Blackbody as a function of energy.
beta1d 1-D surface brightness beta-model.
beta2d 2-D Lorentzian with varying power law.
box1d 1-D box function.
box2d 2-D box function.
bpl1d Broken power law function.
C calc_chisqr Calculate the Chi Squared statistic contribution per bin
calc_data_sum2d Calculate the sum of observed image counts
calc_data_sum Calculate the sum of observed data counts
calc_energy_flux Calculate the unconvolved model energy flux
calc_ftest Calculate the significance using the F test
calc_kcorr Calculate the k correction
calc_mlr Calculate the Maximum Likelihood Ratio test
calc_model_sum2d Calculate the convolved 2D model amplitudes
calc_model_sum Calculate the sum of convolved model counts
calc_photon_flux Calculate the unconvolved model photon flux
calc_source_sum2d Calculate the unconvolved 2D model amplitudes
calc_source_sum Calculate the sum of unconvolved model amplitudes
calc_stat Calculate the fit statistic by data set ID
cash A maximum likelihood function.
chi2constvar Chi-square statistic with constant variance computed from the counts data.
chi2datavar Chi-square statistic with variance computed from the data.
chi2gehrels Chi-square statistic with the Gehrels variance function.
chi2modvar Chi-square statistic with variance computed from model amplitudes.
chi2xspecvar Chi-square statistic with variance computed from data amplitudes.
chisquare About the chi-square statistic.
clean Erase data and model settings in a Sherpa session
const1d 1-D constant amplitude model.
const2d 2-D constant amplitude model.
contour_data Open a contour plot of a data set in ChIPS
contour_fit_resid Create a contour plot of the fit and residuals
contour_fit Send a contour plot of the fit
contour_model Open a contour plot of a data set model in ChIPS
contour_psf Create a contour plot of a PSF
contour_ratio Open a contour plot of a data-to-model ratio in ChIPS
contour_resid Open a contour plot of data-minus-model residuals in ChIPS
contour_source Create a contour plot of the source
contour Open a contour plot in ChIPS
copy_data Copy a data set by data ID to a new data ID (deep copy)
cos Cosine function.
covariance Estimate confidence intervals for selected thawed parameters based on covariance method
create_model_component Create a new model component
cstat A maximum likelihood function
D dataspace1d Create a blank 1D dataset
dataspace2d Create a blank 2D dataset
delete_bkg_model Delete a background model
delete_data Delete a data set by ID
delete_model_component Delete a model component
delete_model Delete a Sherpa model by model ID
delete_psf Delete a PSF model
delta1d 1-D delta function.
delta2d 2-D delta function.
dered Dereddening function.
devaucouleurs2d DeVaucouleurs profile.
E edge Photoabsorption edge model.
eqwidth Calculate the equivalent width of an emission or absorption line.
erfc A 1-D complementary error function.
erf A 1-D error function.
exp10 Exponential function, base 10.
exp Exponential function.
F fake_pha Simulate a PHA dataset with faked counts using Poisson noise
fit Perform a fit using current optimization method and fit statistic.
freeze Freeze model parameters, so they do not vary during a fit.
G gamma Calculate the Gamma function
gauss1d 1-D unnormalized Gaussian function.
gauss2d 2-D unnormalized Gaussian function.
get_analysis Return the current units setting for a PHA data set
get_areascal Return the source or background pixel fractional area scale
get_arf_plot Return the data and preferences defining an ARF plot
get_arf Return a source ARF
get_axes Return the alternate grid of a data set
get_backscal Return the source or background extraction region area
get_bkg_plot Return the data and preferences defining a background plot.
get_bkg Return the background data, ARF, RMF, or model.
get_chisqr_plot Return the data and preferences defining a chi^2 plot
get_coord Return the coordinate system of an image
get_counts Return the dependent variable array (e.g., counts) of a data set
get_covar Return settings or results for the covariance method.
get_data_plot Return a plot, contour, or image of the data, or the associated preferences
get_data Return details of a Sherpa data set by ID.
get_default_id Return the default data set ID in a Sherpa session.
get_delchi_plot Return the data and preferences defining a delta chi plot
get_dep Return the dependent variable array (e.g., counts) of a data set
get_dims Return the length of the x-dimension of a data set
get_error Return the total errors on the counts of a data set
get_exposure Return the exposure time for a source or background data set
get_filter Return the filter of a data set
get_fit Return model fit information associated with a Sherpa data set.
get_indep Return the independent variable array of a data set
get_int_proj Return the confidence data defining an interval projection plot
get_int_unc Return the confidence data defining an int_unc() plot
get_method Return information on the optimization method
get_model_autoassign_func Return the method for storing model identifiers
get_model_plot Return a plot, contour, or image of a model, or the associated preferences
get_model Return the model, model parameters, or model type
get_num_par Returns the number of parameters (total, frozen, or thawed) in a model.
get_order_plot Return the data and preferences defining a plot of model spectral orders
get_par Returns a model parameter.
get_pileup_model Return the pileup model associated with a data set.
get_proj Return information regarding the projection method.
get_psf Return PSF model data and plot, image, and contour preferences.
get_rate Return the measured count rate of a data set
get_ratio Return information on the ratio of data and model.
get_reg_proj Return the confidence data defining a region projection contour plot
get_reg_unc Return the confidence data defining a reg_unc() contour plot
get_resid Return information on a contour plot of the residuals of data and model.
get_rmf Return a Sherpa RMF data set by ID
get_source Return the unconvolved model associated with a Sherpa data set ID.
get_specresp Return the effective area of a PHA spectrum
get_split_plot Return plot attributes for multiple plots
get_staterror Return the statistical errors on the counts of a data set
get_stat Return information on the fit statistic
get_syserror Return the systematic errors on the counts of a data set
group Enable and specify the grouping settings of a spectral data set
guess Estimate initial parameter values and ranges
H histogram1d Create a 1D histogram from a binned grid and array of samples
histogram2d Create a 2D histogram from a pair of axes and a pair of sample arrays
hubblereynolds Hubble-Reynolds profile.
I igamc Calculate the compliment of the incomplete Gamma function (upper)
igam Calculate the incomplete Gamma function (lower)
ignore2d_id Apply an exclude region filter to 2-D data by data set ID(s).
ignore2d Apply an exclude region filter to all 2-D data sets
ignore_bad Ignore bins according to quality flags
ignore_id Apply an exclude filter to 1-D data by data set ID
ignore Apply an exclude filter to all 1D data sets
image_close Close the imager window (i.e., exit ds9).
image_data Send image of 2-D data to ds9.
image_deleteframes Delete frames in the imager window (ds9).
image_fit Send image of the fit results to ds9.
image_getregion Returns a region description from ds9.
image_model Send image of the model to ds9.
image_open Open the imager window (i.e., start ds9).
image_psf Send a PSF image to the imager (ds9).
image_ratio Send image of the ratio (i.e., data/model) to ds9.
image_resid Send image of the residuals (i.e., data - model) to ds9.
image_setregion Sends a region description to ds9, where it is drawn in the current frame.
image_source Image the 2-D unconvolved model
image_xpaget Retrieve data from ds9 using XPA.
image_xpaset Send data to ds9 using XPA.
incbet Calculate the incomplete Beta function
integrate Controlling the integration of model components
int_proj Create a confidence plot of fit statistic vs. parameter value.
int_unc Create a confidence plot of fit statistic vs. parameter value.
J jdpileup A CCD pileup model developed by John Davis of MIT.
L leastsq Chi-square statistic with variance set to 1.
levmar Levenberg-Marquardt optimization method
lgam Calculate the log of the Gamma function
linebroad Line-broadening profile.
link Link a model parameter to another model parameter.
list_bkg_ids List all background IDs associated with a data set.
list_data_ids List all data set IDs in a Sherpa session.
list_functions List all available Sherpa functions
list_methods List all Sherpa optimization methods.
list_models List all Sherpa models.
list_model_components List all models established in a Sherpa session.
list_model_ids List all current model IDs.
list_response_ids List all response IDs associated with a data set.
list_stats List all Sherpa fit statistics.
load_arf Load a source or background ARF
load_arrays Load data from variables containing arrays.
load_ascii Load ASCII data
load_bkg_arf Load a background ARF
load_bkg_rmf Load a background RMF
load_bkg Load a PHA background spectrum
load_data Load 1D data from a file
load_image Load an image
load_multi_arfs Load multiple ARFs
load_multi_rmfs Load multiple RMFs
load_pha Load PHA source spectra
load_psf Load a PSF model
load_rmf Load a source or background RMF
load_table_model Load data into a table model
load_table Load tabular data
load_user_model Load a user-defined model
log10 Logarithm function, base 10.
log Natural logarithm function.
lorentz1d 1-D normalized Lorentzian function.
lorentz2d 2-D unnormalized Lorentzian function.
M models Summary of Available Models
moncar Monte Carlo optimization method
N neldermead Nelder-Mead Simplex optimization method
normbeta1d 1-D normalized beta function.
normgauss1d 1-D normalized Gaussian function.
notice2d_id Apply an include filter to 2D data by dataset id
notice2d Apply an include filter to all 2D datasets
notice_id Apply an include filter to 1D data by dataset id
notice Apply an include filter to all 1D datasets
P pack_image Pack image data into an IMAGECrate
pack_pha Pack PHA data into a PHACrate
pack_table Pack tabular data into a TABLECrate
plot_arf Plot an ARF
plot_bkg Plot information about background data
plot_chisqr Plot the chi-squared statistic
plot_data Plot the dataset
plot_delchi Plot the delchi residuals of the fit: (data-model)/error
plot_fit Plot the fit, fit plus delta chi, or fit plus residuals
plot_model Plot the convolved source model
plot_order Plot the convolved source model by order
plot_psf Plot the PSF
plot_ratio Plot the (data/model) ratio
plot_resid Plot the residuals of the fit: (data - model)
plot_source Plot the unconvolved source model
plot Plot multiple objects (data, model, residuals, etc.)
poisson Poisson function.
polynom1d 1-D polynomial function.
polynom2d 2-D polynomial function.
powlaw1d 1-D power law.
projection Estimate confidence intervals for selected thawed parameters based on projection method
R rebin Rebin a histogram
reg_proj Create a confidence contour of fit statistic vs. two thawed parameter values.
reg_unc Create a confidence contour of fit statistic vs. two thawed parameter values.
reset Reset model parameter values after a fit
restore Restore a previous Sherpa session from a file
S save_data Save a Sherpa data set to an ASCII file.
save_image Save image data to a file
save_pha Save a Sherpa data set to a PHA file.
save_table Save a Sherpa data set to a FITS or ASCII file.
save Save the current Sherpa session to a file
schechter Schechter function.
script Save every command typed in a Sherpa session to a file.
set_analysis Set the units for spectral analysis
set_areascal Set the fractional area
set_arf Set an ARF dataset
set_backscal Set the extraction region area
set_bkg_model Set a background model expression
set_bkg Set a background PHA dataset
set_coord Set the image coordinate system
set_counts Set the dependent variable (e.g. counts) of a dataset
set_covar_opt Set the options for covariance
set_data Set a source dataset
set_default_id Set the default Sherpa data id
set_exposure Set the exposure time
set_grouping Apply user-defined grouping to a dataset
set_method_opt Set the options of the chosen optimization method
set_method Set the optimization method
set_model_autoassign_func Define a method for storing model identifiers
set_model Set the model expression to be used for fitting a dataset
set_par Set initial values for a model parameter
set_pileup_model Set a pileup model to be used in fitting a dataset
set_proj_opt Set the options for projection
set_psf Convolve the PSF model with the source model
set_rmf Set an RMF dataset
set_source Set the source model expression to be used for fitting a dataset
set_staterror Set the statistical errors
set_stat Set the statistical method
set_syserror Set the systematic errors
sherpacl How to start SherpaCL, the CIAO 3.4-like interface to Sherpa and ChIPS in CIAO 4
sherparc The .sherpa.rc file provides user-configuration options for Sherpa
sherpa Introduction to Sherpa, the CIAO modeling and fitting package
show_all Reports the current state of the Sherpa session
show_covar Display the covariance information
show_data Display the data sets
show_filter Display the filters applied to a dataset
show_fit Display the fit information
show_method Display the optimization method
show_model Display the convolved source model
show_proj Display the projection information
show_source Display the unconvolved source model
show_stat Display the fit statistic
sin Sine function.
sqrt Square root function.
stephi1d 1-D step function.
steplo1d 1-D step function.
subtract Perform background subtraction
T tablemodel Using an n-dimensional array of values as a model (table model).
tan Tangent function.
thaw Thaw model parameters so they vary during a fit
U ungroup Ungroup PHA data
unlink Remove a link between model parameters
unpack_arf Unpack an ARF from an ARFCrate
unpack_arrays Unpack arrays from a CrateData object
unpack_ascii Unpack ASCII data from a crate
unpack_bkg Unpack PHA data from a PHACrate
unpack_data Unpack a table data, ASCII data, or a spectrum from a crate
unpack_image Unpack image data from an IMAGECrate
unpack_pha Unpack PHA data from a PHACrate
unpack_rmf Unpack an RMF from a crate
unpack_table Unpack tabular data from a TABLECrate
unsubtract Undo background subtraction
X 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.
xsbkn2pow Broken power law, two break energies. 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.
xscompps Comptonization, Poutanen and Svenson. 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.
xsdiskir Irradiated inner and outer disk. 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.
xsdiskpbb Accretion disk, power-law dependence for T(r). 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.
xsezdiskbb Multiple blackbody disk model with zero-torque inner boundary. 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.
xskerrbb Multi-temperature blackbody model for thin accretion disk around a Kerr black hole. XSpec model.
xskerrdisk Accretion disk line emission with BH spin as free parameter. XSpec model.
xskerrd Optically thick accretion disk around a Kerr black hole. XSpec model.
xslaor2 Accretion disk with broken-power law emissivity profile, black hole emission line. 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.
xsnsagrav NS H atmosphere model for different g. XSpec model.
xsnsatmos NS Hydrogen Atmosphere model with electron conduction and self-irradiation. XSpec model.
xsnsa Spectra in the X-ray range (0.05-10 keV) emitted from a hydrogen atmosphere of a neutron star. XSpec model.
xsnsmax Neutron Star Magnetic Atmosphere. XSpec model.
xsnteea Pair plasma model. XSpec model.
xsnthcomp Thermally comptonized continuum. XSpec model.
xspcfabs Partial covering fraction absorption. XSpec model.
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.
xsspexpcut Super-exponential cutoff absorption. 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.
xssss_ice Einstein SSS ice absorption. XSpec model.
xsstep Step function convolved with gaussian. XSpec model.
xsswind1 Absorption by partially ionized material with large velocity shear. 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.
xszdust Extinction by dust grains. 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.
xszredden Redshifted version of redden. XSpec model.
xszsmdust Extinction by dust grains in starburst galaxies. 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.
xszxipcf Partial covering absorption by partially ionized material. XSpec model.
xs XSpec model functions.

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Last modified: 3 November 2009


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