?

Show the valid options. Does not set $xspec_tclout.

areascal n <s|b>

Writes a string of blank separated values giving the AREASCAL values for spectrum n.  If no second argument is given or it is “s” then the values are from the source file, if “b” from the background file.

arf n

The auxiliary response filename(s) for spectrum n.

backgrnd n

Background filename for spectrum n

backscal n <s|b>

Same as areascal option but for BACKSCAL value.

chain best|last|proposal|stat

The best option returns the parameter values corresponding to the smallest statistic value in the loaded chains. The last option returns the final set of parameter values in the loaded chains. The proposal option takes arguments distribution or matrix and returns the name or covariance matrix for the proposal distribution when using Metropolis-Hastings. The stat option returns the output of the last chain stat command.

chatter

Current xspec chatter level.

compinfo [<mod>:]n [<groupn>]

Name, 1^st parameter number and number of parameters of model component n, belonging to model w/ optional name <mod> and optional datagroup <groupn>.

cosmo

Writes a blank separated string containing the Hubble constant (H0), the deceleration parameter (q0), and the cosmological constant (Lambda0).  Note that if Lambda0 is non-zero the Universe is assumed to be flat and the value of q0 should be ignored.

covariance [m, n]

Element (m,n) from the covariance matrix of the most recent fit.  If no indices are specified, then entire covariance matrix is retrieved.

datagrp [n]

Data group number for spectrum n.  If no n is given, outputs the total number of data groups.

datasets

Number of datasets.

dof

Degrees of freedom in fit, and the number of channels.

energies [n]

Writes a string of blank separated values giving the energies for spectrum n on which the model is calculated.  If n is not specified or is 0, it will output the energies of the default dummy response matrix.

eqwidth n [errsims]

Last equivalent width calculated for spectrum n.  If “errsims” keyword is supplied, this will instead return the complete sorted array of values generated for the most recent eqwidth error simulation.

error [<mod>:]n

(for gain parameters use:

rerror [<sourceNum>:]n )

Writes last confidence region calculated for parameter n of model with optional name <mod>, and a string listing any errors that occurred during the calculation.  The string comprises nine letters, the letter is T or F depending on whether or not an error occurred.  The 9 possible errors are:

1.  new minimum found

2.  non-monotonicity detected

3.  minimization may have run into problem

4.  hit hard lower limit

5.  hit hard upper limit

6.  parameter was frozen

7.  search failed in –ve direction

8.  search failed in +ve direction

9.  reduced chi-squared too high

So for example an error string of “FFFFFFFFT” indicates the calculation failed because the reduced chi-squared was too high.

expos n <s|b>

Same as areascal option but for EXPOSURE value.

filename n

Filename corresponding to spectrum n.

flux [n] [errsims]

Last model flux or luminosity calculated for spectrum n.  Writes a string of 6 values: val errLow errHigh (in ergs/cm²) val errLow errHigh (in photons).  Error values are .0 if flux was not run with “err” option.

If the “errsims” keyword is supplied, this will instead return the completed sorted array of values generated during the most recent flux error calculation.

ftest

The result of the last ftest command.

gain [<sourceNum>:] <specNum> slope | offset

For gain fit parameters, value,delta,min,low,high,max for the slope or offset parameter belonging to the [<sourceNum>:]<specNum> response.  For nonfit gain parameters, only the value is returned.

goodness [sims]

The percentage of realizations from the last goodness command with statistic value less than the best-fit statistic using the data.  If optional “sims” keyword is specified, this will instead give the full array of simulation values from the last goodness command.

idline e d

Possible line IDs within the range [e-d, e+d].

ignore [<n>]

The range(s) of the ignored channels for spectrum <n>.

lumin [n] [errsims]

Last model luminosity calculated for spectrum n.  Same output format as flux option, in units of 1.0x10⁴⁴ erg/s.

margin probability |  [<modName>:]<parNum>

The probability option returns the probability column respectively from the most recent margin command.  Otherwise, the parameter column indicated by <parNum> is returned.  Note that for multi-dimensional margin the returned parameter column will contain duplicate values, in the same order as they originally appeared on the screen during the margin run.

model

Description of current model(s).

modcomp [<mod>]

Number of components in model (with optional model name).

modpar [<mod>]

Number of model parameters (with optional model name).

modval [<specNum>[<mod]]

Write to Tcl the last calculated model values for the specified spectrum and optional model name.  Writes a string of blank separated numbers.  Note that the output is in units of photons/cm^2/s/bin.

nchan [<n>]

Total number of channels in spectrum n (including ignored channels).

noticed [<n>]

Range (low,high) of noticed channels for spectrum n.

noticed energy [<n>]

The noticed energies for spectrum n.

nullhyp

When using chi-square for fits, this will retrieve the reported null hypothesis probability.

param [<mod>:]n

(value,delta,min,low,high,max) for model parameter n.

peakrsid n [lo, hi]

Energies and strengths of the peak residuals (+ve and –ve) for the spectrum n. Optional arguments lo, hi specify an energy range in which to search.

pinfo [<mod>:]n

Parameter name and unit for parameter n of model with optional name.

plink [<mod>:]n

Information on parameter linking for parameter n. This is in the form true/false (T or F) for linked/not linked, followed by the multiplicative factor and additive constants if linked.

plot <option> <array>     [<plot group n>]

Write a string of blank separated values for the array.  <option> is one of the valid arguments for the plot or iplot commands.  <array> is one of x, xerr, y, yerr, or model.  xerr and yerr output the 1-sigma error bars generated for plots with errors.  The model array is for the convolved model in data and ldata plots.  For contour plots this command just dumps the steppar results.  The command does not work for genetic plot options.

plotgrp

Number of plot groups.

query

The setting of the query option.

rate <n | all>

Count rate, uncertainty and the model rate for the specified spectrum n, or for the sum over all spectra.

rerror [<sourceNumber>:]n

Writes last confidence region calculated for response parameter n of model with optional source number, and a string listing any errors that occurred during the calculation. See the help above on the error option for a description of the string.

response n

Response filename(s) for the spectrum n.

sigma [<modelName>:]n

The sigma uncertainty value for parameter n.  If n is not a variable parameter or fit was unable to calculate sigma, -1.0 is returned.

simpars

Creates a list of parameter values by drawing from a multivariate Normal distribution based on the covariance matrix from the last fit.  This is the same mechanism that is used to get the errors on fluxes and luminosities, and to run the goodness command.

solab

Solar abundance table values.

stat [test]

Value of statistic.  If optional ‘test’ argument is given, this outputs the test statistic rather than the fit statistic.

statmethod [test]

The name of the fit stat method currently in use.  If optional ‘test’ argument is given, this will give the name of the test stat method.

steppar  statistic | delstat | [<modName>:]<parNum>

The statistic and delstat options return the statistic or delta-statistic column respectively from the most recent steppar run.  Otherwise, the parameter column indicated by <parNum> is returned.  Note that for multi-dimensional steppars the returned parameter column will contain duplicate values, in the same order as they originally appeared on the screen during the steppar run.

varpar

Number of variable fit parameters.

version

The XSPEC version string.

weight

Name of the current weighting function.

xflt n

XFLT#### keywords for spectrum n. The first number written is the number of keywords and the rest are the keyword values.